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                                                                 Exhibit 4.5

                                                                   EXHIBIT C
                                                                   ---------

NEITHER THESE SECURITIES NOR THE SECURITIES INTO WHICH THESE SECURITIES ARE
EXERCISABLE HAVE BEEN REGISTERED WITH THE SECURITIES AND EXCHANGE COMMISSION
OR THE SECURITIES COMMISSION OF ANY STATE IN RELIANCE UPON AN EXEMPTION FROM
REGISTRATION UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES
ACT"), AND, ACCORDINGLY, MAY NOT BE OFFERED OR SOLD EXCEPT PURSUANT TO AN
EFFECTIVE REGISTRATION STATEMENT UNDER THE SECURITIES ACT OR PURSUANT TO AN
AVAILABLE EXEMPTION FROM, OR IN A TRANSACTION NOT SUBJECT TO, THE
REGISTRATION REQUIREMENTS OF THE SECURITIES ACT AND IN ACCORDANCE WITH
APPLICABLE STATE SECURITIES LAWS AS EVIDENCED BY A LEGAL OPINION OF COUNSEL
TO THE TRANSFEROR TO SUCH EFFECT, THE SUBSTANCE OF WHICH SHALL BE REASONABLY
ACCEPTABLE TO THE COMPANY. THESE SECURITIES AND THE SECURITIES ISSUABLE UPON
EXERCISE OF THESE SECURITIES MAY BE PLEDGED IN A MANNER CONSISTENT WITH THE
SECURITIES ACT IN CONNECTION WITH A BONA FIDE MARGIN ACCOUNT SECURED BY SUCH
SECURITIES.

                           ZOLTEK COMPANIES, INC.

                                   WARRANT

Warrant No. __                   Date of Original Issuance: October 14, 2004

         Zoltek Companies, Inc., a Missouri corporation (the "COMPANY"),
hereby certifies that, for value received, ___________ or its registered
assigns (the "HOLDER"), is entitled to purchase from the Company up to a
total of ____________ shares of common stock, par value $0.01 per share (the
"COMMON STOCK"), of the Company (each such share, a "WARRANT SHARE" and all
such shares, the "WARRANT SHARES") at an exercise price equal to $13.00 per
share (as adjusted from time to time as provided in Section 9, the "EXERCISE
PRICE"), at any time and from time to time from and after the date hereof
and through and including October 14, 2010 (the "EXPIRATION DATE"), and
subject to the following terms and conditions:

         1. Definitions. In addition to the terms defined elsewhere in this
            -----------
Warrant, capitalized terms that are not otherwise defined herein shall have
the meanings given to such terms in the Loan and Warrant Agreement, dated as
of October 14, 2004 to which the Company and the original Holder are parties
(the "PURCHASE AGREEMENT").

         2. Registration of Warrant. The Company shall register this
            -----------------------
Warrant, upon records to be maintained by the Company for that purpose (the
"WARRANT REGISTER"), in the name of the record Holder hereof from time to
time. The Company may deem and treat the registered Holder of this Warrant
as the absolute owner hereof for the purpose of any exercise hereof or any
distribution to the Holder, and for all other purposes, absent actual notice
to the contrary.

         3. Registration of Transfers. The Company shall register the
            -------------------------
transfer of any portion of this Warrant in the Warrant Register, upon
surrender of this Warrant, with the Form of Assignment attached hereto duly
completed and signed, to the Company at its address specified herein. Upon
any such registration or transfer, a new Warrant to purchase Common Stock,
in substantially the form of this Warrant (any such new Warrant, a "NEW
WARRANT"), evidencing the portion of this Warrant so transferred shall be
issued to the transferee and a New Warrant evidencing the remaining portion
of this Warrant not so transferred, if any, shall be issued to the
transferring Holder. The acceptance of the New Warrant by the transferee
thereof shall be deemed the acceptance by such transferee of all of the
rights and obligations of a holder of a Warrant.

         4. Exercise and Duration of Warrants. This Warrant shall be
            ---------------------------------
exercisable by the registered Holder at any time and from time to time on or
after the date hereof to and including the Expiration Date. At 6:30 p.m.,
New York City time on the Expiration Date, the portion of this Warrant not
exercised prior thereto shall be and become void and of no value, provided,
                                                                  --------
that if the closing sales price of the Common Stock on the Expiration Date
is greater than 102% of the Exercise Price on the Expiration Date, then this
Warrant shall be deemed to have been exercised in full (to the extent not
previously exercised) on a "cashless exercise" basis at 6:30 P.M. New York
City time on the Expiration Date. The Company may not call or redeem all or
any portion of this Warrant without the prior written consent of the Holder.

         5. Delivery of Warrant Shares.
            --------------------------

            (a) To effect exercises hereunder, the Holder shall not be required
to physically surrender this Warrant unless the aggregate Warrant Shares
represented by this Warrant is being exercised. Upon delivery of the
Exercise Notice to the Company (with the attached Warrant Shares Exercise
Log) at its address for notice set forth herein and upon payment of the
Exercise Price multiplied by the number of Warrant Shares that the Holder
intends to purchase hereunder, the Company shall promptly (but in no event
later than three Trading Days after the Date of Exercise (as defined
herein)) issue and deliver to the Holder, a certificate for the Warrant
Shares issuable upon such exercise, which, unless otherwise required by the
Purchase Agreement, shall be free of restrictive legends. The Company shall,
upon request of the Holder and subsequent to the date on which a
registration statement covering the resale of the Warrant Shares has been
declared effective by the Securities and Exchange Commission, use its best
efforts to deliver Warrant Shares hereunder electronically through The
Depository Trust Corporation or another established clearing corporation
performing similar functions, if available, provided, that, the Company may,
but will not be required to change its transfer agent if its current
transfer agent cannot deliver Warrant Shares electronically through the
Depository Trust Corporation. A "DATE OF EXERCISE" means the date on which
the Holder shall have delivered to Company: (i) the Exercise Notice (with
the Warrant Exercise Log attached to it), appropriately completed and duly
signed and (ii) if such Holder is not utilizing the cashless exercise
provisions set forth in this Warrant, payment of the Exercise Price for the
number of Warrant Shares so indicated by the Holder to be purchased.

            (b) If by the third Trading Day after a Date of Exercise the
Company fails to deliver the required number of Warrant Shares in the manner
required pursuant to Section 5(a), then the Holder will have the right to
rescind such exercise.

                                     2

            (c) If by the third Trading Day after a Date of Exercise the
Company fails to deliver the required number of Warrant Shares in the manner
required pursuant to Section 5(a), and if after such third Trading Day and
prior to the receipt of such Warrant Shares, the Holder purchases (in an
open market transaction or otherwise) shares of Common Stock to deliver in
satisfaction of a sale by the Holder of the Warrant Shares which the Holder
anticipated receiving upon such exercise (a "BUY-IN"), then the Company
shall (1) pay in cash to the Holder the amount by which (x) the Holder's
total purchase price (including brokerage commissions, if any) for the
shares of Common Stock so purchased exceeds (y) the amount obtained by
multiplying (A) the number of Warrant Shares that the Company was required
to deliver to the Holder in connection with the exercise at issue by (B) the
closing bid price of the Common Stock at the time of the obligation giving
rise to such purchase obligation and (2) at the option of the Holder, either
reinstate the portion of the Warrant and equivalent number of Warrant Shares
for which such exercise was not honored or deliver to the Holder the number
of shares of Common Stock that would have been issued had the Company timely
complied with its exercise and delivery obligations hereunder. The Holder
shall provide the Company written notice indicating the amounts payable to
the Holder in respect of the Buy-In.

            (d) The Company's obligations to issue and deliver Warrant Shares
in accordance with the terms hereof are absolute and unconditional,
irrespective of any action or inaction by the Holder to enforce the same,
any waiver or consent with respect to any provision hereof, the recovery of
any judgment against any Person or any action to enforce the same, or any
setoff, counterclaim, recoupment, limitation or termination, or any breach
or alleged breach by the Holder or any other Person of any obligation to the
Company or any violation or alleged violation of law by the Holder or any
other Person, and irrespective of any other circumstance which might
otherwise limit such obligation of the Company to the Holder in connection
with the issuance of Warrant Shares. Nothing herein shall limit a Holder's
right to pursue any other remedies available to it hereunder, at law or in
equity including, without limitation, a decree of specific performance
and/or injunctive relief with respect to the Company's failure to timely
deliver certificates representing shares of Common Stock upon exercise of
the Warrant as required pursuant to the terms hereof.

         6. Charges, Taxes and Expenses. Issuance and delivery of
            ---------------------------
certificates for shares of Common Stock upon exercise of this Warrant shall
be made without charge to the Holder for any issue or transfer tax,
withholding tax, transfer agent fee or other incidental tax or expense in
respect of the issuance of such certificates, all of which taxes and
expenses shall be paid by the Company; provided, however, that the Company
shall not be required to pay any tax which may be payable in respect of any
transfer involved in the registration of any certificates for Warrant Shares
or Warrants in a name other than that of the Holder. The Holder shall be
responsible for all other tax liability that may arise as a result of
holding or transferring this Warrant or receiving Warrant Shares upon
exercise hereof.

         7. Replacement of Warrant. If this Warrant is mutilated, lost,
            ----------------------
stolen or destroyed, the Company shall issue or cause to be issued in
exchange and substitution for and upon cancellation hereof, or in lieu of
and substitution for this Warrant, a New Warrant, but only upon receipt of
evidence reasonably satisfactory to the Company of such loss, theft or
destruction and customary and reasonable indemnity (which may include a
surety bond for any Holder other than the original Holder of the Warrant),
if requested. Applicants for a New Warrant under such

                                     3

circumstances shall also comply with such other reasonable regulations and
procedures and pay such other reasonable third-party costs as the Company
may prescribe. If a New Warrant is requested as a result of a mutilation of
this Warrant, then the Holder shall deliver such mutilated Warrant to the
Company as a condition precedent to the Company's obligation to issue the
New Warrant.

         8. Reservation of Warrant Shares. The Company covenants that it
            -----------------------------
will at all times reserve and keep available out of the aggregate of its
authorized but unissued and otherwise unreserved Common Stock, solely for
the purpose of enabling it to issue Warrant Shares upon exercise of this
Warrant as herein provided, the number of Warrant Shares which are then
issuable and deliverable upon the exercise of this entire Warrant, free from
preemptive rights or any other contingent purchase rights of persons other
than the Holder (taking into account the adjustments and restrictions of
Section 9). The Company covenants that all Warrant Shares so issuable and
---------
deliverable shall, upon issuance and the payment of the applicable Exercise
Price in accordance with the terms hereof, be duly and validly authorized,
issued and fully paid and nonassessable.

         9. Certain Adjustments. The Exercise Price and number of Warrant
            -------------------
Shares issuable upon exercise of this Warrant are subject to adjustment from
time to time as set forth in this Section 9.
                                  ---------

            (a) Stock Dividends and Splits. If the Company, at any time while
                --------------------------
this Warrant is outstanding, (i) pays a stock dividend on its Common Stock
or otherwise makes a distribution on any class of capital stock that is
payable in shares of Common Stock, (ii) subdivides outstanding shares of
Common Stock into a larger number of shares, or (iii) combines outstanding
shares of Common Stock into a smaller number of shares, then in each such
case the Exercise Price shall be multiplied by a fraction of which the
numerator shall be the number of shares of Common Stock outstanding
immediately before such event and of which the denominator shall be the
number of shares of Common Stock outstanding immediately after such event.
Any adjustment made pursuant to clause (i) of this paragraph shall become
effective immediately after the record date for the determination of
shareholders entitled to receive such dividend or distribution, and any
adjustment pursuant to clause (ii) or (iii) of this paragraph shall become
effective immediately after the effective date of such subdivision or
combination. If any event requiring an adjustment under this paragraph
occurs during the period that an Exercise Price is calculated hereunder,
then the calculation of such Exercise Price shall be adjusted appropriately
to reflect such event.

            (b) Pro Rata Distributions. If the Company, at any time while this
                ----------------------
Warrant is outstanding, distributes to all holders of Common Stock (i)
evidences of its indebtedness, (ii) any security (other than a distribution
of Common Stock covered by the preceding paragraph), (iii) rights or
warrants to subscribe for or purchase any security, or (iv) any other asset
(in each case, "DISTRIBUTED PROPERTY"), then, at the request of any Holder
delivered before the 90th day after the record date fixed for determination
of shareholders entitled to receive such distribution, the Company will
deliver to such Holder, within five Trading Days after such request (or, if
later, on the effective date of such distribution), the Distributed Property
that such Holder would have been entitled to receive in respect of the
Warrant Shares for which such Holder's Warrant could have been exercised
immediately prior to such record date. If such Distributed Property is

                                     4

not delivered to a Holder pursuant to the preceding sentence, then upon any
exercise of the Warrant that occurs after such record date, such Holder
shall be entitled to receive, in addition to the Warrant Shares otherwise
issuable upon such conversion, the Distributed Property that such Holder
would have been entitled to receive in respect of such number of Warrant
Shares had the Holder been the record holder of such Warrant Shares
immediately prior to such record date. Notwithstanding the foregoing, this
Section 9(b) shall not apply to any distribution of rights or securities in
respect of adoption by the Company of a shareholder rights plan which events
shall be covered by the anti-dilution provisions of Section 9(a).

            (c) Fundamental Transactions. If, at any time while this Warrant
                ------------------------
is outstanding, (1) the Company effects any merger or consolidation of the
Company with or into another Person, (2) the Company effects any sale of all
or substantially all of its assets in one or a series of related
transactions, (3) any tender offer or exchange offer approved or authorized
by the Board of Directors of the Company (whether by the Company or another
Person) is completed pursuant to which holders of Common Stock are permitted
to tender or exchange their shares for other securities, cash or property,
or (4) the Company effects any reclassification of the Common Stock or any
compulsory share exchange pursuant to which the Common Stock is effectively
converted into or exchanged for other securities, cash or property (in any
such case, a "FUNDAMENTAL TRANSACTION"), then the Holder shall have the
right thereafter to receive, upon exercise of this Warrant, the same amount
and kind of securities, cash or property as it would have been entitled to
receive upon the occurrence of such Fundamental Transaction if it had been,
immediately prior to such Fundamental Transaction, the holder of the number
of Warrant Shares then issuable upon exercise in full of this Warrant (the
"ALTERNATE CONSIDERATION"). For purposes of any such exercise, the
determination of the Exercise Price shall be appropriately adjusted to apply
to such Alternate Consideration based on the amount of Alternate
Consideration issuable in respect of one share of Common Stock in such
Fundamental Transaction, and the Company shall apportion the Exercise Price
among the Alternate Consideration in a reasonable manner reflecting the
relative value of any different components of the Alternate Consideration.
If holders of Common Stock are given any choice as to the securities, cash
or property to be received in a Fundamental Transaction, then the Holder
shall be given the same choice as to the Alternate Consideration it receives
upon any exercise of this Warrant following such Fundamental Transaction. At
the Holder's option and request, any successor to the Company or surviving
entity in such Fundamental Transaction shall, either (1) issue to the Holder
a new warrant substantially in the form of this Warrant and consistent with
the foregoing provisions and evidencing the Holder's right to purchase the
Alternate Consideration for the aggregate Exercise Price upon exercise
thereof, or (2) purchase the Warrant from the Holder for a purchase price,
payable in cash within five Trading Days after such request (or, if later,
on the effective date of the Fundamental Transaction), equal to the Black
Scholes value of the remaining unexercised portion of this Warrant on the
date of such request as well as assumptions reasonably mutually acceptable
to the Company and the Holder, provided, that for purposes of such
                               --------
calculation, the market price of the Common Stock shall be the closing bid
price of the Common Stock on the Trading Day immediately preceding the
public announcement of the Fundamental Transaction and the volatility factor
shall be determined by reference to the 12 month average industry volatility
measures. The terms of any agreement pursuant to which a Fundamental
Transaction is effected shall include terms requiring any such successor or
surviving entity to comply with the provisions of this paragraph (c) and

                                     5

insuring that the Warrant (or any such replacement security) will be
similarly adjusted upon any subsequent transaction analogous to a
Fundamental Transaction.

            (d) Subsequent Equity Sales.(1)
                -----------------------

                (i)   While any portion of this Warrant is outstanding,
if the Company issues any shares of Common Stock or the Company or any
subsidiary thereof issues any rights, warrants, options or other securities
or debt that is convertible into, exchangeable for (any such securities,
"COMMON STOCK EQUIVALENTS") entitling any Person to acquire shares of Common
Stock, at a price per share less than the Exercise Price (if the holder of
the Common Stock or Common Stock Equivalent so issued shall at any time,
whether by operation of purchase price adjustments, reset provisions,
floating conversion, exercise or exchange prices or otherwise, or due to
warrants, options or rights issued in connection with such issuance, be
entitled to receive shares of Common Stock at a price less than the Exercise
Price, such issuance shall be deemed to have occurred for less than the
Exercise Price), then, at the option of the Holder for such exercises as it
shall indicate, the Exercise Price shall be adjusted to equal the
conversion, exchange or purchase price for such Common Stock or Common Stock
Equivalents (including any reset provisions thereof) at issue and which
adjusted Exercise Price shall continue for as long as this Warrants remain
outstanding. Such adjustment shall be made whenever such Common Stock or
Common Stock Equivalents are issued. The Company shall notify the Holder in
writing, no later than the Trading Day following the issuance of any Common
Stock or Common Stock Equivalent subject to this section, indicating therein
the applicable issuance price, or of applicable reset price, exchange price,
conversion price and other pricing terms.

                (ii)  For purposes of this subsection 9(d), the following
subsections (d)(ii)(l) to (d)(ii)(6) shall also be applicable:

                      (1) Issuance of Rights or Options. In case at any time
                          -----------------------------
the Company shall in any manner grant (directly and not by assumption in a
merger or otherwise) any warrants or other rights to subscribe for or to
purchase, or any options for the purchase of, Common Stock or any stock or
security convertible into or exchangeable for Common Stock (such warrants,
rights or options being called "OPTIONS" and such convertible or
exchangeable stock or securities being called "CONVERTIBLE SECURITIES")
whether or not such Options or the right to convert or exchange any such
Convertible Securities are immediately exercisable, and the price per share
for which Common Stock is issuable upon the exercise of such Options or upon
the conversion or exchange of such Convertible Securities (determined by
dividing (i) the sum (which sum shall constitute the applicable
consideration) of (x) the total amount, if any, received or receivable by
the Company as consideration for the granting of such Options, plus (y) the
aggregate amount of additional consideration payable to the Company upon the
exercise of all such Options, plus (z), in the case of such Options which
relate to Convertible Securities, the aggregate amount of additional
consideration, if any, payable upon the issue or sale of such Convertible
Securities and upon the conversion or exchange thereof, by (ii) the total
maximum number of shares of Common Stock issuable upon the exercise of such
Options or upon the conversion or exchange of all such Convertible
Securities issuable upon the exercise of such

<FN>
--------
(1) This provision will not be in the Warrants issued to directors or
    officers of the Company.

                                     6

Options) shall be less than the Exercise Price in effect immediately prior
to the time of the granting of such Options, then the total number of shares
of Common Stock issuable upon the exercise of such Options or upon
conversion or exchange of the total amount of such Convertible Securities
issuable upon the exercise of such Options shall be deemed to have been
issued for such price per share as of the date of granting of such Options
or the issuance of such Convertible Securities and thereafter shall be
deemed to be outstanding for purposes of adjusting the Exercise Price.
Except as otherwise provided in subsection 9(d)(ii)(3), no adjustment of the
Exercise Price shall be made upon the actual issue of such Common Stock or
of such Convertible Securities upon exercise of such Options or upon the
actual issue of such Common Stock upon conversion or exchange of such
Convertible Securities.

                      (2) Issuance of Convertible Securities. In case the
                          ----------------------------------
Company shall in any manner issue (directly and not by assumption in a
merger or otherwise) or sell any Convertible Securities, whether or not the
rights to exchange or convert any such Convertible Securities are
immediately exercisable, and the price per share for which Common Stock is
issuable upon such conversion or exchange (determined by dividing (i) the
sum (which sum shall constitute the applicable consideration) of (x) the
total amount received or receivable by the Company as consideration for the
issue or sale of such Convertible Securities, plus (y) the aggregate amount
of additional consideration, if any, payable to the Company upon the
conversion or exchange thereof, by (ii) the total number of shares of Common
Stock issuable upon the conversion or exchange of all such Convertible
Securities) shall be less than the Exercise Price in effect immediately
prior to the time of such issue or sale, then the total maximum number of
shares of Common Stock issuable upon conversion or exchange of all such
Convertible Securities shall be deemed to have been issued for such price
per share as of the date of the issue or sale of such Convertible Securities
and thereafter shall be deemed to be outstanding for purposes of adjusting
the Exercise Price, provided that (a) except as otherwise provided in
subsection 9(d)(ii)(3), no adjustment of the Exercise Price shall be made
upon the actual issuance of such Common Stock upon conversion or exchange of
such Convertible Securities and (b) no further adjustment of the Exercise
Price shall be made by reason of the issue or sale of Convertible Securities
upon exercise of any Options to purchase any such Convertible Securities for
which adjustments of the Exercise Price have been made pursuant to the other
provisions of subsection 9(d).

                      (3) Change in Option Price or Conversion Rate. Upon the
                          -----------------------------------------
happening of any of the following events, namely, if the purchase price
provided for in any Option referred to in subsection 9(d)(ii)(l) hereof, the
additional consideration, if any, payable upon the conversion or exchange of
any Convertible Securities referred to in subsections 9(d)(ii)(l) or
9(d)(ii)(2), or the rate at which Convertible Securities referred to in
subsections 9(d)(ii)(l) or 9(d)(ii)(2) are convertible into or exchangeable
for Common Stock shall change at any time (including, but not limited to,
changes under or by reason of provisions designed to protect against
dilution), the Exercise Price in effect at the time of such event shall
forthwith be readjusted to the Exercise Price which would have been in
effect at such time had such Options or Convertible Securities still
outstanding provided for such changed purchase price, additional
consideration or conversion rate, as the case may be, at the time initially
granted, issued or sold. On the termination of any Option for which any
adjustment was made pursuant to this subsection 9(d) or any right to convert
or exchange Convertible Securities for which any adjustment was made
pursuant to this subsection 9(d) (including without limitation upon the
redemption or

                                     7

purchase for consideration of such Convertible Securities by the Company),
the Exercise Price then in effect hereunder shall forthwith be changed to
the Exercise Price which would have been in effect at the time of such
termination had such Option or Convertible Securities, to the extent
outstanding immediately prior to such termination, never been issued.

                      (4) Stock Dividends. Subject to the provisions of this
                          ---------------
Section 9(d), in case the Company shall declare a dividend or make any other
distribution upon any stock of the Company (other than the Common Stock)
payable in Common Stock, Options or Convertible Securities, then any Common
Stock, Options or Convertible Securities, as the case may be, issuable in
payment of such dividend or distribution shall be deemed to have been issued
or sold without consideration.

                      (5) Consideration for Stock. In case any shares of
                          -----------------------
Common Stock, Options or Convertible Securities shall be issued or sold for
cash, the consideration received therefor shall be deemed to be the net
amount received by the Company therefor, after deduction therefrom of any
expenses incurred or any underwriting commissions or concessions paid or
allowed by the Company in connection therewith. In case any shares of Common
Stock, Options or Convertible Securities shall be issued or sold for a
consideration other than cash, the amount of the consideration other than
cash received by the Company shall be deemed to be the fair value of such
consideration as determined in good faith by the Board of Directors of the
Company, after deduction of any expenses incurred or any underwriting
commissions or concessions paid or allowed by the Company in connection
therewith. In case any Options shall be issued in connection with the issue
and sale of other securities of the Company, together comprising one
integral transaction in which no specific consideration is allocated to such
Options by the parties thereto, such Options shall be deemed to have been
issued for such consideration as determined in good faith by the Board of
Directors of the Company. If Common Stock, Options or Convertible Securities
shall be issued or sold by the Company and, in connection therewith, other
Options or Convertible Securities (the "ADDITIONAL RIGHTS") are issued, then
the consideration received or deemed to be received by the Company shall be
reduced by the fair market value of the Additional Rights (as determined
using the Black-Scholes option pricing model or another method mutually
agreed to by the Company and the Holder). The Board of Directors of the
Company shall respond promptly, in writing, to an inquiry by the Holders as
to the fair market value of the Additional Rights. In the event that the
Board of Directors of the Company and the Holders are unable to agree upon
the fair market value of the Additional Rights, the Company and the Holders
shall jointly select an appraiser, who is experienced in such matters. The
decision of such appraiser shall be final and conclusive, and the cost of
such appraiser shall be borne evenly by the Company and the Holder.

                      (6) Record Date. In case the Company shall take a
                          -----------
record of the holders of its Common Stock for the purpose of entitling them
(i) to receive a dividend or other distribution payable in Common Stock,
Options or Convertible Securities or (ii) to subscribe for or purchase
Common Stock, Options or Convertible Securities, then such record date shall
be deemed to be the date of the issue or sale of the shares of Common Stock
deemed to have been issued or sold upon the declaration of such dividend or
the making of such other distribution or the date of the granting of such
right of subscription or purchase, as the case may be.

                                     8

                (iii) Notwithstanding the foregoing, no adjustment will be
made under this Section 9(d) as a result of: (i) the issuance of securities
upon the exercise or conversion of any Common Stock Equivalents issued by
the Company prior to the date of this Agreement (but will apply to any
amendments, modifications and reissuances thereof), (ii) the grant of
options or warrants, or the issuance of additional securities, under any
duly authorized company stock option, stock incentive plan, restricted stock
plan or stock purchase plan in existence on the Closing Date, (iii) the
issuance of Common Stock in payment of interest on the Notes or on the 2003
Debentures or 2004 Debentures, or (iv) the issuance of Common Stock
Equivalents pursuant to a Strategic Transaction.

            (e) Number of Warrant Shares. Simultaneously with any adjustment
                ------------------------
to the Exercise Price pursuant to paragraph (a) of this Section, the number
of Warrant Shares that may be purchased upon exercise of this Warrant shall
be increased or decreased proportionately, so that after such adjustment the
aggregate Exercise Price payable hereunder for the adjusted number of
Warrant Shares shall be the same as the aggregate Exercise Price in effect
immediately prior to such adjustment.

            (f) Calculations. All calculations under this Section 9 shall be
                ------------                              ---------
made to the nearest cent or the nearest 1/100th of a share, as applicable.
The number of shares of Common Stock outstanding at any given time shall not
include shares owned or held by or for the account of the Company, and the
disposition of any such shares shall be considered an issue or sale of
Common Stock.

            (g) Notice of Adjustments. Upon the occurrence of each adjustment
                ---------------------
pursuant to this Section 9, the Company at its expense will promptly compute
                 ---------
such adjustment in accordance with the terms of this Warrant and prepare a
certificate setting forth such adjustment, including a statement of the
adjusted Exercise Price and adjusted number or type of Warrant Shares or
other securities issuable upon exercise of this Warrant (as applicable),
describing the transactions giving rise to such adjustments and showing in
detail the facts upon which such adjustment is based. Upon written request,
the Company will promptly deliver a copy of each such certificate to the
Holder and to the Company's transfer agent.

            (h) Notice of Corporate Events. If the Company (i) declares a
                --------------------------
dividend or any other distribution of cash, securities or other property in
respect of its Common Stock, including without limitation any granting of
rights or warrants to subscribe for or purchase any capital stock of the
Company or any Subsidiary, (ii) authorizes or approves, enters into any
agreement contemplating or solicits shareholder approval for any Fundamental
Transaction or (iii) authorizes the voluntary dissolution, liquidation or
winding up of the affairs of the Company, then the Company shall deliver to
the Holder a notice describing the material terms and conditions of such
transaction, at least 20 calendar days prior to the applicable record or
effective date on which a Person would need to hold Common Stock in order to
participate in or vote with respect to such transaction, and the Company
will take all steps reasonably necessary in order to insure that the Holder
is given the practical opportunity to exercise this Warrant prior to such
time so as to participate in or vote with respect to such transaction;
provided, however, that the failure to deliver such notice or any defect
therein shall not affect the validity of the corporate action required to be
described in such notice.

                                     9

         10. Payment of Exercise Price. The Holder may pay the Exercise
             -------------------------
Price in one of the following manners:

             (a) Cash Exercise. The Holder may deliver immediately available
                 -------------
funds; or

             (b) Cashless Exercise. The Holder may notify the Company in an
                 -----------------
Exercise Notice of its election to utilize cashless exercise, in which event
the Company shall issue to the Holder the number of Warrant Shares
determined as follows:

                       X = Y [(A-B)/A]

                 where:

                       X = the number of Warrant Shares to be issued to the
                       Holder.

                       Y = the number of Warrant Shares with respect to which
                       this Warrant is being exercised.

                       A = the average of the closing prices for the five
                       Trading Days immediately prior to (but not including)
                       the Exercise Date.

                       B = the Exercise Price.

For purposes of Rule 144 promulgated under the Securities Act, it is
intended, understood and acknowledged that the Warrant Shares issued in a
cashless exercise transaction shall be deemed to have been acquired by the
Holder, and the holding period for the Warrant Shares shall be deemed to
have commenced, on the date this Warrant was originally issued.

         11. Limitations on Exercise.
             -----------------------

                 (i)   Notwithstanding anything to the contrary contained
herein, the number of shares of Common Stock that may be acquired by the
Holder upon any exercise of this Warrant (or otherwise in respect hereof)
shall be limited to the extent necessary to insure that, following such
exercise (or other issuance), the total number of shares of Common Stock
then beneficially owned by such Holder and its Affiliates and any other
Persons whose beneficial ownership of Common Stock would be aggregated with
the Holder's for purposes of Section 13(d) of the Exchange Act, does not
exceed 9.999% of the total number of issued and outstanding shares of Common
Stock (including for such purpose the shares of Common Stock issuable upon
such exercise). For such purposes, beneficial ownership shall be determined
in accordance with Section 13(d) of the Exchange Act and the rules and
regulations promulgated thereunder. This provision shall not restrict the
number of shares of Common Stock which a Holder may receive or beneficially
own in order to determine the amount of securities or other consideration
that such Holder may receive in the event of a Fundamental Transaction
involving the Company as contemplated in Section 9 of this Warrant. This
restriction may not be waived.

                 (ii)  Notwithstanding anything to the contrary in this
Warrant, if the Company has not previously obtained Shareholder Approval (as
defined below), then the Company may not issue shares of Common Stock in
excess of the Issuable Maximum upon

                                     10

exercises of this Warrant at a conversion price which is less than the
Closing Price on the Trading Day immediately preceding the Original Issue
Date (the "THRESHOLD PRICE"). The "Issuable Maximum" means, as of any date,
a number of shares of Common Stock equal to 3,289,196, less such number of
shares of Common Stock as have been issued at a price below the Threshold
Price (1) upon exercise of this Warrant and warrants issued under the 2003
Securities Purchase Agreement and the 2004 Securities Purchase Agreement,
(2) upon conversion of the 2003 Debentures and the 2004 Debentures, and (3)
upon conversion of Notes, or in payment of interests thereunder. Each Holder
shall be entitled to a portion of the Issuable Maximum equal to the quotient
obtained by dividing: (x) the principal amount of Notes issued and sold to
such Holder on the Original Issue Date under the Purchase Agreement by (y)
the aggregate principal amount of all Notes issued and sold by the Company
on the Original Issue Date. If any Holder shall no longer hold Notes, then
such Holder's remaining portion of the Issuable Maximum (other than those
represented by the remaining portion of this Warrant and the other warrants
referenced in clause (1) above) shall be allocated pro-rata among the
remaining Holders, giving effect to the Company's desire to allocate among
the class of securities known as the Notes this limitation. If on any Date
of Exercise, or at such time as a Holder shall notify the Company that the
condition in (A) following this clause shall be in effect: (A) the aggregate
number of shares of Common Stock that would then be issuable upon exercise
in full of this Warrant would exceed the Issuable Maximum on such date, and
(B) the Company shall not have previously obtained the vote of shareholders,
as may be required by the applicable rules and regulations of the Nasdaq
Stock Market (or any successor entity or any other Eligible Market on which
the Company's securities then trade), applicable to approve the issuance of
shares of Common Stock in excess of the Issuable Maximum pursuant to the
terms hereof (the "SHAREHOLDER APPROVAL"), then, the Company shall issue
upon exercise hereof a number of shares of Common Stock equal to the
Issuable Maximum and, with respect to the remainder of this Warrant for
which an exercise would result in an issuance of shares of Common Stock in
excess of the Issuable Maximum, the Company must seek Shareholder Approval
as soon as possible, but in any event not later than the 90th day following
such Date of Exercise or the date of such request. The Company and the
Holder understand and agree that shares of Common Stock issued to and then
held by the Holder as a result of exercises of this Warrant shall not be
entitled to cast votes on any resolution to obtain Shareholder Approval
pursuant hereto.

         12. No Fractional Shares. No fractional shares of Warrant Shares will
             --------------------
be issued in connection with any exercise of this Warrant. In lieu of any
fractional shares which would, otherwise be issuable, the Company shall pay
cash equal to the product of such fraction multiplied by the closing price
of one Warrant Share as reported by the applicable Trading Market on the
date of exercise.

         13. Notices. Any and all notices or other communications or deliveries
             -------
hereunder (including, without limitation, any Exercise Notice) shall be in
writing and shall be deemed given and effective on the earliest of (i) the
date of transmission, if such notice or communication is delivered via
facsimile at the facsimile number specified in this Section prior to 6:30
p.m. (New York City time) on a Trading Day, (ii) the next Trading Day after
the date of transmission, if such notice or communication is delivered via
facsimile at the facsimile number specified in this Section on a day that is
not a Trading Day or later than 6:30 p.m. (New York City time) on any
Trading Day, (iii) the Trading Day following the date of mailing, if sent by
nationally recognized overnight courier service, or (iv) upon actual receipt
by the party to whom

                                     11

such notice is required to be given. The addresses for such communications
shall be: (i) if to the Company, to Zoltek Companies, Inc., 3101 McKelvey
Road, St. Louis, Missouri 63044, Attn: Chief Financial Officer, Facsimile
No.: (314) 291-9082, or (ii) if to the Holder, to the address or facsimile
number appearing on the Warrant Register or such other address or facsimile
number as the Holder may provide to the Company in accordance with this
Section.

         14. Warrant Agent. The Company shall serve as warrant agent under this
             -------------
Warrant. Upon 30 days' notice to the Holder, the Company may appoint a new
warrant agent. Any corporation into which the Company or any new warrant
agent may be merged or any corporation resulting from any consolidation to
which the Company or any new warrant agent shall be a party or any
corporation to which the Company or any new warrant agent transfers
substantially all of its corporate trust or shareholders services business
shall be a successor warrant agent under this Warrant without any further
act. Any such successor warrant agent shall promptly cause notice of its
succession as warrant agent to be mailed (by first class mail, postage
prepaid) to the Holder at the Holder's last address as shown on the Warrant
Register.

         15. Miscellaneous.
             -------------

             (a) This Warrant shall be binding on and inure to the benefit
of the parties hereto and their respective successors and assigns. Subject
to the preceding sentence, nothing in this Warrant shall be construed to
give to any Person other than the Company and the Holder any legal or
equitable right, remedy or cause of action under this Warrant. This Warrant
may be amended only in writing signed by the Company and the Holder and
their successors and assigns.

             (b) All questions concerning the construction, validity,
enforcement and interpretation of this Warrant shall be governed by and
construed and enforced in accordance with the internal laws of the State of
New York, without regard to the principles of conflicts of law thereof. Each
party agrees that all legal proceedings concerning the interpretations,
enforcement and defense of this Warrant and the transactions herein
contemplated ("PROCEEDINGS") (whether brought against a party hereto or its
respective Affiliates, employees or agents) shall be commenced exclusively
in the state and federal courts sitting in the City of New York, Borough of
Manhattan (the "NEW YORK COURTS"). Each party hereto hereby irrevocably
submits to the exclusive jurisdiction of the New York Courts for the
adjudication of any dispute hereunder or in connection herewith or with any
transaction contemplated hereby or discussed herein, and hereby irrevocably
waives, and agrees not to assert in any Proceeding, any claim that it is not
personally subject to the jurisdiction of any New York Court, or that such
Proceeding has been commenced in an improper or inconvenient forum. Each
party hereto hereby irrevocably waives personal service of process and
consents to process being served in any such Proceeding by mailing a copy
thereof via registered or certified mail or overnight delivery (with
evidence of delivery) to such party at the address in effect for notices to
it under this Warrant and agrees that such service shall constitute good and
sufficient service of process and notice thereof. Nothing contained herein
shall be deemed to limit in any way any right to serve process in any manner
permitted by law. Each party hereto hereby irrevocably waives, to the
fullest extent permitted by applicable law, any and all right to trial by
jury in any legal proceeding arising out of or relating to this Warrant or
the transactions contemplated hereby. If either party shall commence a
Proceeding to enforce any provisions of this Warrant, then the

                                     12

prevailing party in such Proceeding shall be reimbursed by the other party
for its attorney's fees and other costs and expenses incurred with the
investigation, preparation and prosecution of such Proceeding.

             (c) The headings herein are for convenience only, do not
constitute a part of this Warrant and shall not be deemed to limit or affect
any of the provisions hereof.

             (d) In case any one or more of the provisions of this Warrant
shall be invalid or unenforceable in any respect, the validity and
enforceability of the remaining terms and provisions of this Warrant shall
not in any way be affected or impaired thereby and the parties will attempt
in good faith to agree upon a valid and enforceable provision which shall be
a commercially reasonable substitute therefor, and upon so agreeing, shall
incorporate such substitute provision in this Warrant.

                [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK,
                           SIGNATURE PAGE FOLLOWS]

                                     13

         IN WITNESS WHEREOF, the Company has caused this Warrant to be duly
executed by its authorized officer as of the date first indicated above.

                                         ZOLTEK COMPANIES, INC.

                                          By:
                                             ----------------------------
                                             Name:
                                             Title:

                                     14

                               EXERCISE NOTICE

To ZOLTEK COMPANIES, INC.:

         The undersigned hereby irrevocably elects to purchase _____________
shares of common stock, par value $0.01 per share, of ZOLTEK COMPANIES, INC.
("COMMON STOCK"), pursuant to Warrant No. 1, originally issued October 14,
2004 (the "WARRANT"), and, if such Holder is not utilizing the cashless
exercise provisions set forth in the Warrant, encloses herewith $________ in
cash, certified or official bank check or checks or other immediately
available funds, which sum represents the aggregate Exercise Price (as
defined in the Warrant) for the number of shares of Common Stock to which
this Exercise Notice relates, together with any applicable taxes payable by
the undersigned pursuant to the Warrant.

         By its delivery of this Exercise Notice, the undersigned represents
and warrants to the Company that in giving effect to the exercise evidenced
hereby the Holder will not beneficially own in excess of the number of
shares of Common Stock (determined in accordance with Section 13(d) of the
Securities Exchange Act of 1934) permitted to be owned under Section 11 of
this Warrant to which this notice relates.

         The undersigned requests that certificates for the shares of Common
Stock issuable upon this exercise be issued in the name of

                                      PLEASE INSERT SOCIAL SECURITY OR
                                      TAX IDENTIFICATION NUMBER

                       (Please print name and address)

                                     15

<TABLE>
                               Warrant Shares Exercise Log
                               ---------------------------

<CAPTION>
-----------------------------------------------------------------------------------------
Date         Number of Warrant          Number of Warrant Shares     Number of Warrant
             Shares Available to be     Exercised                    Shares Remaining to
             Exercised                                               be Exercised
-----------------------------------------------------------------------------------------
<S>          <C>                        <C>                          <C>

-----------------------------------------------------------------------------------------
</TABLE>

                                     16

                             FORM OF ASSIGNMENT

         [To be completed and signed only upon transfer of Warrant]

         FOR VALUE RECEIVED, the undersigned hereby sells, assigns and
transfers unto ________________________________ the right represented by the
within Warrant to purchase ____________ shares of Common Stock of ZOLTEK
COMPANIES, INC. to which the within Warrant relates and appoints
________________ attorney to transfer said right on the books of the Company
with full power of substitution in the premises.

Dated:   _______________, ____

                                     ---------------------------------------
                                     (Signature must conform in all respects
                                     to name of holder as specified on the
                                     face of the Warrant)

                                     ---------------------------------------
                                     Address of Transferee

                                     ---------------------------------------

                                     ---------------------------------------

In the presence of:

--------------------------

                                     17<PAGE>

                                                                 Exhibit 4.6

                                                                   EXHIBIT B
                                                                   ---------

                        REGISTRATION RIGHTS AGREEMENT

                  This Registration Rights Agreement (this "AGREEMENT") is
made and entered into as of October 14, 2004, by and among Zoltek Companies,
Inc., a Missouri corporation (the "COMPANY"), and the investors signatory
hereto (each a "INVESTOR" and collectively, the "INVESTORS").

                  This Agreement is made pursuant to the Loan and Warrant
Agreement, dated as of October 14, 2004, among the Company and the Investors
(the "PURCHASE AGREEMENT").

                  The Company and the Investors hereby agree as follows:

         1.       Definitions. Capitalized terms used and not otherwise defined
                  -----------
herein that are defined in the Purchase Agreement shall have the meanings
given such terms in the Purchase Agreement. As used in this Agreement, the
following terms shall have the respective meanings set forth in this Section 1:

                  "EFFECTIVE DATE" means the date that the Registration
Statement filed pursuant to Section 2(a) is first declared effective by the
Commission.

                  "EFFECTIVENESS DATE" means: (a) with respect to the
initial Registration Statement required to be filed to cover the resale by
the Holders of the Registrable Securities, the earlier of: (a)(i) the 90th
day following the Closing Date; provided, that, if the Commission reviews
                                --------
and has written comments to the filed Registration Statement that would
require the filing of a pre-effective amendment thereto with the Commission,
then the Effectiveness Date under this clause (a)(i) shall be the 120th day
following the Closing Date, and (ii) the fifth Trading Day following the
date on which the Company is notified by the Commission that the initial
Registration Statement will not be reviewed or is no longer subject to
further review and comments, and (b) with respect to any additional
Registration Statements that may be required pursuant to Section 2(b)
hereof, the earlier of: (i) the 90th day following the date on which the
Company first knows, or reasonably should have known, that such additional
Registration Statement is required under such Section; provided, that, if
                                                       --------
the Commission reviews and has written comments to such filed Registration
Statement that would require the filing of a pre-effective amendment thereto
with the Commission, then the Effectiveness Date under this clause (b)(i)
shall be the 120th day following the date that the Company first knows, or
reasonably should have known, that such additional Registration Statement is
required under such Section, and (ii) the fifth Trading Day following the
date on which the Company is notified by the Commission that such additional
Registration Statement will not be reviewed or is no longer subject to
further review and comments.

                  "EFFECTIVENESS PERIOD" shall have the meaning set forth in
Section 2(a).

                                    -1-

                  "EXCHANGE ACT" means the Securities Exchange Act of 1934,
as amended.

                  "FILING DATE" means: (a) with respect to the initial
Registration Statement required to be filed to cover the resale by the
Holders of the Registrable Securities, the 30th day following the Closing
Date, and (b) with respect to any additional Registration Statements that
may be required pursuant to Section 2(b) hereof, the 30th day following the
date on which the Company first knows, or reasonably should have known, that
such additional Registration Statement is required under such Section.

                  "HOLDER" or "HOLDERS" means the holder or holders, as the
case may be, from time to time of Registrable Securities.

                  "INDEMNIFIED PARTY" shall have the meaning set forth in
Section 5(c).

                  "INDEMNIFYING PARTY" shall have the meaning set forth in
Section 5(c).

                  "LOSSES" shall have the meaning set forth in Section 5(a).

                  "NOTES" means, collectively, each of the senior secured
convertible promissory notes, due on the date that is 42 months after the
Closing Date, each issuable by the Company to one of the Lenders (as defined
in the Purchase Agreement) pursuant to the Purchase Agreement.

                  "PROCEEDING" means an action, claim, suit, investigation
or proceeding (including, without limitation, an investigation or partial
proceeding, such as a deposition), whether commenced or threatened.

                  "PROSPECTUS" means the prospectus included in a
Registration Statement (including, without limitation, a prospectus that
includes any information previously omitted from a prospectus filed as part
of an effective registration statement in reliance upon Rule 430A
promulgated under the Securities Act), as amended or supplemented by any
prospectus supplement, with respect to the terms of the offering of any
portion of the Registrable Securities covered by a Registration Statement,
and all other amendments and supplements to the Prospectus, including
post-effective amendments, and all material incorporated by reference or
deemed to be incorporated by reference in such Prospectus.

                  "REGISTRABLE SECURITIES" means the Underlying Shares
issuable upon (a) conversion of the Notes (assuming such Notes are held
until the maturity date thereof and all interest is accreted to principal
thereunder), and (b) upon exercise of the Warrants, together in each case of
(a) and (b) above with any securities issued or issuable upon any stock
split, dividend or other distribution, recapitalization or similar event, or
any conversion price adjustment with respect thereto.

                  "REGISTRATION STATEMENT" means each of the following: (i)
an initial registration statement which is required to register the resale
of the Registrable Securities, (ii) each additional registration statement,
if any, contemplated by Section 2(b), and including, in each case, the
Prospectus, amendments and supplements to each such

                                    -2-

registration statement or Prospectus, including pre- and post-effective
amendments, all exhibits thereto, and all material incorporated by reference
or deemed to be incorporated by reference in such registration statement.

                  "RULE 144" means Rule 144 promulgated by the Commission
pursuant to the Securities Act, as such Rule may be amended from time to
time, or any similar rule or regulation hereafter adopted by the Commission
having substantially the same effect as such Rule.

                  "RULE 415" means Rule 415 promulgated by the Commission
pursuant to the Securities Act, as such Rule may be amended from time to
time, or any similar rule or regulation hereafter adopted by the Commission
having substantially the same effect as such Rule.

                  "RULE 424" means Rule 424 promulgated by the Commission
pursuant to the Securities Act, as such Rule may be amended from time to
time, or any similar rule or regulation hereafter adopted by the Commission
having substantially the same effect as such Rule.

                  "SECURITIES ACT" means the Securities Act of 1933, as
amended.

                  "WARRANTS" has the meaning ascribed in the Purchase
Agreement.

         2.       Registration.
                  ------------

                  (a) On or prior to each Filing Date, the Company shall
prepare and file with the Commission a Registration Statement covering the
resale of all Registrable Securities not already covered by an existing and
effective Registration Statement for an offering to be made on a continuous
basis pursuant to Rule 415. The Registration Statement shall be on Form S-3
(except if the Company is not then eligible to register for resale the
Registrable Securities on Form S-3, in which case such registration shall be
on another appropriate form for such purpose) and shall contain (except if
otherwise required pursuant to written comments received from the Commission
upon a review of such Registration Statement) the "Plan of Distribution"
substantially in the form attached hereto as Annex A. The Company shall
                                             -------
cause each Registration Statement to be declared effective under the
Securities Act as soon as possible but, in any event, no later than its
Effectiveness Date, and shall use its best efforts to keep each Registration
Statement continuously effective under the Securities Act until the sixth
year after the date that the Registration Statement is declared effective by
the Commission or such earlier date when all Registrable Securities covered
by the Registration Statement have been sold or may be sold without volume
restrictions pursuant to Rule 144(k) as determined by the counsel to the
Company pursuant to a written opinion letter to such effect, addressed and
acceptable to the Company's transfer agent and the affected Holders (the
"EFFECTIVENESS PERIOD"). The initial Registration Statement shall include a
number of Registrable Securities equal to the sum of (a) the number of
Underlying Shares issuable upon an assumed conversion in full of the Notes
(assuming for such purpose that the Conversion Price is 75% of the
conversion price on the Closing Date, the Notes are held until their full
Maturity Dates

                                    -3-

and all interest accretes to principal for the life thereof), and (b) the
number of Underlying Shares issuable upon a conversion in full of the
Warrants (assuming for such purpose that the exercise price of the Warrants
is 75% of the exercise price on the Closing Date, as such sum may be
required to be reduced pursuant to written comments to the Registration
Statement received from the Commission.

                  (b) If for any reason the Commission does not permit all of
the Registrable Securities to be included in the Registration Statement
filed pursuant to Section 2(a) or for any other reason all Registrable
Securities then outstanding are not then included in an effective
Registration Statement, then the Company shall prepare and file as soon as
possible after the date on which the Commission shall indicate as being the
first date or time that such filing may be made, but in any event by the
30th day following such date, an additional Registration Statement covering
the resale of all Registrable Securities not already covered by an existing
and effective Registration Statement for an offering to be made on a
continuous basis pursuant to Rule 415, on Form S-3 (except if the Company is
not then eligible to register for resale the Registrable Securities on Form
S-3, in which case such registration shall be on another appropriate form
for such purpose). Each such Registration Statement shall contain (except if
otherwise required pursuant to written comments received from the Commission
upon a review of such Registration Statement) the "Plan of Distribution"
attached hereto as Annex A. The Company shall cause each such Registration
                   -------
Statement to be declared effective under the Securities Act as soon as
possible but, in any event, no later than the 90th day following the date on
which the Company becomes aware that such Registration Statement is required
to be filed under this Agreement, and shall use its best efforts to keep
such Registration Statement continuously effective under the Securities Act
during the entire Effectiveness Period.

                  (c) If: (i) a Registration Statement is not filed on or
prior to its Filing Date (if the Company files a Registration Statement
without affording the Holders the opportunity to review and comment on the
same as required by Section 3(a) hereof, the Company shall not be deemed to
have satisfied this clause (i)), or (ii) a Registration Statement is not
declared effective by the Commission on or prior to its required
Effectiveness Date, or (iii) after the Effective Date, such Registration
Statement ceases for any reason to be effective or the prospectus thereunder
ceases to available to the Holders as to all Registrable Securities to which
it is required to cover at any time prior to the expiration of its
Effectiveness Period for an aggregate of more than an aggregate of 20
Trading Days (which need not be consecutive, (any such failure or breach
being referred to as an "EVENT," and for purposes of clauses (i) or (ii) the
date on which such Event occurs, or for purposes of clause (iii) the date
which such 20 Trading Day-period is exceeded, being referred to as "EVENT
DATE"), then, in addition to any other rights available to the Holders under
the Transaction Documents or under applicable law: (x) on each such Event
Date and on each monthly anniversary of each such Event Date thereof (if the
applicable Event shall not have been cured by such date) until the
applicable Event is cured, the Company shall pay to each Holder an amount in
cash, as liquidated damages and not as a penalty, equal to 1.5% of the
aggregate Loan Amount loaned by such Holder pursuant to the Purchase
Agreement. If the Company fails to pay any liquidated damages pursuant to
this Section in full within seven days after the date payable, the Company
will

                                    -4-

pay interest thereon at a rate of 12% per annum (or such lesser maximum
amount that is permitted to be paid by applicable law) to the Holder,
accruing daily from the date such liquidated damages are due until such
amounts, plus all such interest thereon, are paid in full. The liquidated
damages pursuant to the terms hereof shall apply on a pro rata basis for any
portion of a month prior to the cure of an Event.

         3.       Registration Procedures.
                  -----------------------

                  In connection with the Company's registration obligations
hereunder, the Company shall:

                  (a) Not less than four Trading Days prior to the filing of
a Registration Statement or any related Prospectus or any amendment or
supplement thereto, the Company shall furnish to the Holders copies of all
such documents proposed to be filed which documents (other than those
incorporated by reference) will be subject to the review of such Holders.
The Company shall not file a Registration Statement or any such Prospectus
or any amendments or supplements thereto to which the Holders of a majority
of the Registrable Securities shall reasonably object in good faith.

                  (b) (i) Prepare and file with the Commission such
amendments, including post-effective amendments, to each Registration
Statement and the Prospectus used in connection therewith as may be
necessary to keep such Registration Statement continuously effective as to
the applicable Registrable Securities for its Effectiveness Period and
prepare and file with the Commission such additional Registration Statements
in order to register for resale under the Securities Act all of the
Registrable Securities; (ii) cause the related Prospectus to be amended or
supplemented by any required Prospectus supplement, and as so supplemented
or amended to be filed pursuant to Rule 424; (iii) respond as promptly as
reasonably possible to any comments received from the Commission with
respect to each Registration Statement or any amendment thereto and, as
promptly as reasonably possible provide the Holders true and complete copies
of all correspondence from and to the Commission relating to such
Registration Statement that would not result in the disclosure to the
Holders of material and non-public information concerning the Company; and
(iv) comply in all material respects with the provisions of the Securities
Act and the Exchange Act with respect to the Registration Statements and the
disposition of all Registrable Securities covered by each Registration
Statement.

                  (c) Notify the Holders as promptly as reasonably possible
(and, in the case of (i)(A) below, not less than three Trading Days prior to
such filing) and (if requested by any such Person) confirm such notice in
writing no later than one Trading Day following the day (i)(A) when a
Prospectus or any Prospectus supplement or post-effective amendment to a
Registration Statement is proposed to be filed; (B) when the Commission
notifies the Company whether there will be a "review" of such Registration
Statement and whenever the Commission comments in writing on such
Registration Statement (the Company shall provide true and complete copies
of any such comments all written responses thereto to each Holder that
pertains to such Holder as a Selling Shareholder or to the Plan of
Distribution, but not information which the

                                    -5-

Company believes would constitute material and non-public information); and
(C) with respect to each Registration Statement or any post-effective
amendment, when the same has become effective; (ii) of any request by the
Commission or any other Federal or state governmental authority for
amendments or supplements to a Registration Statement or Prospectus or for
additional information; (iii) of the issuance by the Commission of any stop
order suspending the effectiveness of a Registration Statement covering any
or all of the Registrable Securities or the initiation of any Proceedings
for that purpose; (iv) of the receipt by the Company of any notification
with respect to the suspension of the qualification or exemption from
qualification of any of the Registrable Securities for sale in any
jurisdiction, or the initiation or threatening of any Proceeding for such
purpose; and (v) of the occurrence of any event or passage of time that
makes the financial statements included in a Registration Statement
ineligible for inclusion therein or any statement made in such Registration
Statement or Prospectus or any document incorporated or deemed to be
incorporated therein by reference untrue in any material respect or that
requires any revisions to such Registration Statement, Prospectus or other
documents so that, in the case of such Registration Statement or the
Prospectus, as the case may be, it will not contain any untrue statement of
a material fact or omit to state any material fact required to be stated
therein or necessary to make the statements therein, in light of the
circumstances under which they were made, not misleading.

                  (d) Use its best efforts to avoid the issuance of, or, if
issued, obtain the withdrawal of (i) any order suspending the effectiveness
of a Registration Statement, or (ii) any suspension of the qualification (or
exemption from qualification) of any of the Registrable Securities for sale
in any jurisdiction, at the earliest practicable moment.

                  (e) Furnish to each Holder, without charge, at least one
conformed copy of each Registration Statement and each amendment thereto and
all exhibits to the extent requested by such Person (excluding those
previously furnished or incorporated by reference) promptly after the filing
of such documents with the Commission.

                  (f) Promptly deliver to each Holder, without charge, as
many copies of each Prospectus or Prospectuses (including each form of
prospectus) and each amendment or supplement thereto as such Persons may
reasonably request. The Company hereby consents to the use of such
Prospectus and each amendment or supplement thereto by each of the selling
Holders in connection with the offering and sale of the Registrable
Securities covered by such Prospectus and any amendment or supplement
thereto.

                  (g) Prior to any public offering of Registrable
Securities, use its best efforts to register or qualify or cooperate with
the selling Holders in connection with the registration or qualification (or
exemption from such registration or qualification) of such Registrable
Securities for offer and sale under the securities or Blue Sky laws of all
jurisdictions within the United States, to keep each such registration or
qualification (or exemption therefrom) effective during the Effectiveness
Period and to do any and all other acts or things necessary or advisable to
enable the disposition in such jurisdictions of the Registrable Securities
covered by the Registration Statements; provided, that the Company shall not
                                        --------
be required to qualify generally to do business in any jurisdiction

                                    -6-

where it is not then so qualified or subject the Company to any material tax
in any such jurisdiction where it is not then so subject.

                  (h) Cooperate with the Holders to facilitate the timely
preparation and delivery of certificates representing Registrable Securities
to be delivered to a transferee pursuant to the Registration Statements,
which certificates shall be free, to the extent permitted by the Purchase
Agreement, of all restrictive legends, and to enable such Registrable
Securities to be in such denominations and registered in such names as any
such Holders may request.

                  (i) Upon the occurrence of any event contemplated by
Section 3(c)(v), as promptly as reasonably possible, prepare a supplement or
amendment, including a post-effective amendment, to the affected
Registration Statements or a supplement to the related Prospectus or any
document incorporated or deemed to be incorporated therein by reference, and
file any other required document so that, as thereafter delivered, no
Registration Statement nor any Prospectus will contain an untrue statement
of a material fact or omit to state a material fact required to be stated
therein or necessary to make the statements therein, in light of the
circumstances under which they were made, not misleading.

                  (j) The Company may require each selling Holder to furnish
to the Company a certified statement as to the number of shares of Common
Stock beneficially owned by such Holder and, if requested by the Commission,
the controlling person thereof.

                  (k) The Company has read and understands the conversion
and exercise limitations contained in the Notes and the Warrants and will
not take a position in any Registration Statement or other filing with the
Commission that a Holder is the beneficial owner of more than the percentage
of Common Stock permitted to be beneficially owned by such Holder absent an
affirmative written statement by such Holder to such effect.

         4.       Registration Expenses. All fees and expenses incident to
                  ---------------------
the performance of or compliance with this Agreement by the Company shall be
borne by the Company whether or not any Registrable Securities are sold
pursuant to a Registration Statement. The fees and expenses referred to in
the foregoing sentence shall include, without limitation, (i) all
registration and filing fees (including, without limitation, fees and
expenses (A) with respect to filings required to be made with any Trading
Market on which the Common Stock is then listed for trading, and (B) in
compliance with applicable state securities or Blue Sky laws), (ii) printing
expenses (including, without limitation, expenses of printing certificates
for Registrable Securities and of printing prospectuses if the printing of
prospectuses is reasonably requested by the holders of a majority of the
Registrable Securities included in the Registration Statement), (iii)
messenger, telephone and delivery expenses, (iv) fees and disbursements of
counsel for the Company, (v) Securities Act liability insurance, if the
Company so desires such insurance, and (vi) fees and expenses of all other
Persons retained by the Company in connection with the consummation of the
transactions contemplated by this Agreement.

                                    -7-

In addition, the Company shall be responsible for all of its internal
expenses incurred in connection with the consummation of the transactions
contemplated by this Agreement (including, without limitation, all salaries
and expenses of its officers and employees performing legal or accounting
duties), the expense of any annual audit and the fees and expenses incurred
in connection with the listing of the Registrable Securities on any
securities exchange as required hereunder.

         5.       Indemnification.
                  ---------------

                  (a) Indemnification by the Company. The Company shall,
                      ------------------------------
notwithstanding any termination of this Agreement, indemnify and hold
harmless each Holder, the officers, directors, agents, investment advisors,
partners, members, shareholders and employees of each of them, each Person
who controls any such Holder (within the meaning of Section 15 of the
Securities Act or Section 20 of the Exchange Act) and the officers,
directors, agents and employees of each such controlling Person, to the
fullest extent permitted by applicable law, from and against any and all
losses, claims, damages, liabilities, costs (including, without limitation,
reasonable costs of preparation and reasonable attorneys' fees) and expenses
(collectively, "LOSSES"), as incurred, arising out of or relating to any
untrue or alleged untrue statement of a material fact contained in any
Registration Statement, any Prospectus or any form of prospectus or in any
amendment or supplement thereto or in any preliminary prospectus, or arising
out of or relating to any omission or alleged omission of a material fact
required to be stated therein or necessary to make the statements therein
(in the case of any Prospectus or form of prospectus or supplement thereto,
in light of the circumstances under which they were made) not misleading,
except to the extent, but only to the extent, that (1) such untrue
statements or omissions are based solely upon information regarding such
Holder furnished in writing to the Company by such Holder expressly for use
therein, or to the extent that such information relates to such Holder or
such Holder's proposed method of distribution of Registrable Securities and
was reviewed and expressly approved in writing by such Holder expressly for
use in the Registration Statement, such Prospectus or such form of
Prospectus or in any amendment or supplement thereto (it being understood
that the Holder has approved Annex A hereto for this purpose) or (2) in the
case of an occurrence of an event of the type specified in Section
3(c)(ii)-(v), the use by such Holder of an outdated or defective Prospectus
after the Company has notified such Holder in writing that the Prospectus is
outdated or defective and prior to the receipt by such Holder of an Advice
or an amended or supplemented Prospectus, but only if and to the extent that
following the receipt of the Advice or the amended or supplemented
Prospectus the misstatement or omission giving rise to such Loss would have
been corrected. The Company shall notify the Holders promptly of the
institution, threat or assertion of any Proceeding of which the Company is
aware in connection with the transactions contemplated by this Agreement.

                  (b) Indemnification by Holders. Each Holder shall,
                      --------------------------
severally and not jointly, indemnify and hold harmless the Company, its
directors, officers, agents and employees, each Person who controls the
Company (within the meaning of Section 15 of the Securities Act and Section
20 of the Exchange Act), and the directors, officers, agents or employees of
such controlling Persons, to the fullest extent permitted by applicable

                                    -8-

law, from and against all Losses, as incurred, arising solely out of or based
solely upon: (x) such Holder's failure to comply with the prospectus
delivery requirements of the Securities Act or (y) any untrue statement of a
material fact contained in any Registration Statement, any Prospectus, or
any form of prospectus, or in any amendment or supplement thereto, or
arising solely out of or based solely upon any omission of a material fact
required to be stated therein or necessary to make the statements therein
not misleading to the extent, but only to the extent that, (1) such untrue
statements or omissions are based solely upon information regarding such
Holder furnished in writing to the Company by such Holder expressly for use
therein, or to the extent that such information relates to such Holder or
such Holder's proposed method of distribution of Registrable Securities and
was reviewed and expressly approved in writing by such Holder expressly for
use in the Registration Statement (it being understood that the Holder has
approved Annex A hereto for this purpose), such Prospectus or such form of
Prospectus or in any amendment or supplement thereto or (2) in the case of
an occurrence of an event of the type specified in Section 3(c)(ii)-(v), the
use by such Holder of an outdated or defective Prospectus after the Company
has notified such Holder in writing that the Prospectus is outdated or
defective and prior to the receipt by such Holder of an Advice or an amended
or supplemented Prospectus, but only if and to the extent that following the
receipt of the Advice or the amended or supplemented Prospectus the
misstatement or omission giving rise to such Loss would have been corrected.
In no event shall the liability of any selling Holder hereunder be greater
in amount than the dollar amount of the net proceeds received by such Holder
upon the sale of the Registrable Securities giving rise to such
indemnification obligation.

                  (c) Conduct of Indemnification Proceedings. If any
                      --------------------------------------
Proceeding shall be brought or asserted against any Person entitled to
indemnity hereunder (an "INDEMNIFIED PARTY"), such Indemnified Party shall
promptly notify the Person from whom indemnity is sought (the "INDEMNIFYING
PARTY") in writing, and the Indemnifying Party shall assume the defense
thereof, including the employment of counsel reasonably satisfactory to the
Indemnified Party and the payment of all fees and expenses incurred in
connection with defense thereof; provided, that the failure of any
Indemnified Party to give such notice shall not relieve the Indemnifying
Party of its obligations or liabilities pursuant to this Agreement, except
(and only) to the extent that it shall be finally determined by a court of
competent jurisdiction (which determination is not subject to appeal or
further review) that such failure shall have proximately and materially
adversely prejudiced the Indemnifying Party.

                  An Indemnified Party shall have the right to employ
separate counsel in any such Proceeding and to participate in the defense
thereof, but the fees and expenses of such counsel shall be at the expense
of such Indemnified Party or Parties unless: (1) the Indemnifying Party has
agreed in writing to pay such fees and expenses; (2) the Indemnifying Party
shall have failed promptly to assume the defense of such Proceeding and to
employ counsel reasonably satisfactory to such Indemnified Party in any such
Proceeding; or (3) the named parties to any such Proceeding (including any
impleaded parties) include both such Indemnified Party and the Indemnifying
Party, and such Indemnified Party shall have been advised by counsel that a
conflict of interest is likely to exist if the same counsel were to
represent such Indemnified Party and the

                                    -9-

Indemnifying Party (in which case, if such Indemnified Party notifies the
Indemnifying Party in writing that it elects to employ separate counsel at
the expense of the Indemnifying Party, the Indemnifying Party shall not have
the right to assume the defense thereof and such counsel shall be at the
expense of the Indemnifying Party). The Indemnifying Party shall not be
liable for any settlement of any such Proceeding effected without its
written consent, which consent shall not be unreasonably withheld. No
Indemnifying Party shall, without the prior written consent of the
Indemnified Party, effect any settlement of any pending Proceeding in
respect of which any Indemnified Party is a party, unless such settlement
includes an unconditional release of such Indemnified Party from all
liability on claims that are the subject matter of such Proceeding.

                  All reasonable fees and expenses of the Indemnified Party
(including reasonable fees and expenses to the extent incurred in connection
with investigating or preparing to defend such Proceeding in a manner not
inconsistent with this Section) shall be paid to the Indemnified Party, as
incurred, within ten Trading Days of written notice thereof to the
Indemnifying Party (regardless of whether it is ultimately determined that
an Indemnified Party is not entitled to indemnification hereunder; provided,
that the Indemnifying Party may require such Indemnified Party to undertake
to reimburse all such fees and expenses to the extent it is finally
judicially determined that such Indemnified Party is not entitled to
indemnification hereunder).

                  (d) Contribution. If a claim for indemnification under
                      ------------
Section 5(a) or 5(b) is unavailable to an Indemnified Party (by reason of
public policy or otherwise), then each Indemnifying Party, in lieu of
indemnifying such Indemnified Party, shall contribute to the amount paid or
payable by such Indemnified Party as a result of such Losses, in such
proportion as is appropriate to reflect the relative fault of the
Indemnifying Party and Indemnified Party in connection with the actions,
statements or omissions that resulted in such Losses as well as any other
relevant equitable considerations. The relative fault of such Indemnifying
Party and Indemnified Party shall be determined by reference to, among other
things, whether any action in question, including any untrue or alleged
untrue statement of a material fact or omission or alleged omission of a
material fact, has been taken or made by, or relates to information supplied
by, such Indemnifying Party or Indemnified Party, and the parties' relative
intent, knowledge, access to information and opportunity to correct or
prevent such action, statement or omission. The amount paid or payable by a
party as a result of any Losses shall be deemed to include, subject to the
limitations set forth in Section 5(c), any reasonable attorneys' or other
reasonable fees or expenses incurred by such party in connection with any
Proceeding to the extent such party would have been indemnified for such
fees or expenses if the indemnification provided for in this Section was
available to such party in accordance with its terms.

                  The parties hereto agree that it would not be just and
equitable if contribution pursuant to this Section 5(d) were determined by
pro rata allocation or by any other method of allocation that does not take
into account the equitable considerations referred to in the immediately
preceding paragraph. Notwithstanding the provisions of this Section 5(d), no
Holder shall be required to contribute, in the

                                    -10-

aggregate, any amount in excess of the amount by which the proceeds actually
received by such Holder from the sale of the Registrable Securities subject
to the Proceeding exceeds the amount of any damages that such Holder has
otherwise been required to pay by reason of such untrue or alleged untrue
statement or omission or alleged omission.

                  The indemnity and contribution agreements contained in
this Section are in addition to any liability that the Indemnifying Parties
may have to the Indemnified Parties.

         6.       Miscellaneous
                  -------------

                  (a) Remedies. In the event of a breach by the Company or
                      --------
by a Holder, of any of their obligations under this Agreement, each Holder
or the Company, as the case may be, in addition to being entitled to
exercise all rights granted by law and under this Agreement, including
recovery of damages, will be entitled to specific performance of its rights
under this Agreement. The Company and each Holder agree that monetary
damages would not provide adequate compensation for any losses incurred by
reason of a breach by it of any of the provisions of this Agreement and
hereby further agrees that, in the event of any action for specific
performance in respect of such breach, it shall waive the defense that a
remedy at law would be adequate.

                  (b) No Piggyback on Registrations. Except as and to the
                      -----------------------------
extent specified in Schedule 6(b) hereto, neither the Company nor any of its
                    -------------
security holders (other than the Holders in such capacity pursuant hereto)
may include securities of the Company in a Registration Statement other than
the Registrable Securities, and the Company shall not after the date hereof
enter into any agreement providing any such right to any of its security
holders. Except as and to the extent specified in Schedule 3.1(g) of the
                                                  ---------------
Purchase Agreement, the Company has not previously entered into any
agreement granting any registration rights with respect to any of its
securities to any Person which have not been fully satisfied.

                  (c) Compliance. Each Holder covenants and agrees that it
                      ----------
will comply with the prospectus delivery requirements of the Securities Act
as applicable to it in connection with sales of Registrable Securities
pursuant to the Registration Statement.

                  (d) Discontinued Disposition. Each Holder agrees by its
                      ------------------------
acquisition of such Registrable Securities that, upon receipt of a notice
from the Company of the occurrence of any event of the kind described in
Section 3(c), such Holder will forthwith discontinue disposition of such
Registrable Securities under the Registration Statement until such Holder's
receipt of the copies of the supplemented Prospectus and/or amended
Registration Statement or until it is advised in writing (the "ADVICE") by
the Company that the use of the applicable Prospectus may be resumed, and,
in either case, has received copies of any additional or supplemental
filings that are incorporated or deemed to be incorporated by reference in
such Prospectus or Registration Statement. The Company may provide
appropriate stop orders to enforce the provisions of this paragraph.

                                    -11-

                  (e) Piggy-Back Registrations. If at any time during the
                      ------------------------
Effectiveness Period there is not an effective Registration Statement
covering all of the Registrable Securities and the Company shall determine
to prepare and file with the Commission a registration statement relating to
an offering for its own account or the account of others under the
Securities Act of any of its equity securities, other than on Form S-4 or
Form S-8 (each as promulgated under the Securities Act) or their then
equivalents relating to equity securities to be issued solely in connection
with any acquisition of any entity or business or equity securities issuable
in connection with stock option or other employee benefit plans, then the
Company shall send to each Holder written notice of such determination and,
if within fifteen days after receipt of such notice, any such Holder shall
so request in writing, the Company shall include in such registration
statement all or any part of such Registrable Securities such holder
requests to be registered, subject to customary underwriter cutbacks
applicable to all holders of registration rights. In connection with each
such registration covering an underwritten public offering, (i) the Company
shall select the investment banker(s) and manager(s) (which shall be
nationally recognized) for such offering and (ii) the Holder agrees to enter
into a written agreement with the managing underwriter selected in the
manner herein provided in such form and containing such provisions as are
customary in the securities business for such an arrangement between such
underwriter and selling shareholders, provided, that the Holders shall not
be obligated to refrain or "lock up" from selling any Registrable Securities
or other securities of the Company for any period of time.

                  (f) Amendments and Waivers. The provisions of this
                      ----------------------
Agreement, including the provisions of this sentence, may not be amended,
modified or supplemented, and waivers or consents to departures from the
provisions hereof may not be given, unless the same shall be in writing and
signed by the Company and the Holders of all of the then outstanding
Registrable Securities. Notwithstanding the foregoing, a waiver or consent
to depart from the provisions hereof with respect to a matter that relates
exclusively to the rights of certain Holders and that does not directly or
indirectly affect the rights of other Holders may be given by Holders of at
least 66 2/3% of the Registrable Securities to which such waiver or consent
relates, provided, that the provisions of this sentence may not be amended,
         --------
modified, or supplemented except in accordance with the provisions of the
immediately preceding sentence.

                  (g) Notices. Any and all notices or other communications
                      -------
or deliveries required or permitted to be provided hereunder shall be in
writing and shall be deemed given and effective on the earliest of (i) the
date of transmission, if such notice or communication is delivered via
facsimile at the facsimile telephone number specified in this Section prior
to 6:30 p.m. (New York City time) on a Trading Day, (ii) the Trading Day
after the date of transmission, if such notice or communication is delivered
via facsimile at the facsimile telephone number specified in this Agreement
later than 6:30 p.m. (New York City time) on any date and earlier than 11:59
p.m. (New York City time) on such date, (iii) the Trading Day following the
date of mailing, if sent by nationally recognized overnight courier service,
or (iv) upon actual receipt by the party to whom such notice is required to
be given. The address for such notices and communications shall be as
follows:

                                    -12-

         If to the Company:         Zoltek Companies, Inc.
                                    3101 McKelvey Road
                                    St. Louis, Missouri 63044
                                    Facsimile No.: (314) 291-9082
                                    Attn: Chief Financial Officer

                                    With a copy to:

                                    Thompson Coburn LLP
                                    One US Bank Plaza
                                    St. Louis, Missouri 63101
                                    Facsimile No.: (314) 552-7000
                                    Attn: Thomas A. Litz, Esq.

         If to a Investor:          To the address set forth under such
                                    Investor's name on the signature pages
                                    hereto.

         If to any other Person who is then the registered Holder:

                                    To the address of such Holder as it
                                    appears in the stock transfer books of
                                    the Company

or such other address as may be designated in writing hereafter, in the same
manner, by such Person.

                  (h) Successors and Assigns. This Agreement shall inure to
                      ----------------------
the benefit of and be binding upon the successors and permitted assigns of
each of the parties and shall inure to the benefit of each Holder. The
Company may not assign its rights or obligations hereunder without the prior
written consent of each Holder. Each Holder may assign its respective rights
hereunder in the manner and to the Persons as permitted under the Purchase
Agreement so long as such assignment complies with the Purchaser Agreement.

                  (i) Execution and Counterparts. This Agreement may be
                      --------------------------
executed in any number of counterparts, each of which when so executed shall
be deemed to be an original and, all of which taken together shall
constitute one and the same Agreement. In the event that any signature is
delivered by facsimile transmission, such signature shall create a valid
binding obligation of the party executing (or on whose behalf such signature
is executed) the same with the same force and effect as if such facsimile
signature were the original thereof.

                  (j) Governing Law. All questions concerning the
                      -------------
construction, validity, enforcement and interpretation of this Agreement
shall be governed by and construed and enforced in accordance with the
internal laws of the State of New York, without regard to the principles of
conflicts of law thereof. Each party agrees that all Proceedings concerning
the interpretations, enforcement and defense of the transactions

                                    -13-

contemplated by this Agreement (whether brought against a party hereto or
its respective Affiliates, employees or agents) shall be commenced
exclusively in the state and federal courts sitting in the City of New York,
Borough of Manhattan (the "NEW YORK COURTS"). Each party hereto hereby
irrevocably submits to the exclusive jurisdiction of the New York Courts for
the adjudication of any dispute hereunder or in connection herewith or with
any transaction contemplated hereby or discussed herein, and hereby
irrevocably waives, and agrees not to assert in any Proceeding, any claim
that it is not personally subject to the jurisdiction of any New York Court,
or that such Proceeding has been commenced in an improper or inconvenient
forum. Each party hereto hereby irrevocably waives personal service of
process and consents to process being served in any such Proceeding by
mailing a copy thereof via registered or certified mail or overnight
delivery (with evidence of delivery) to such party at the address in effect
for notices to it under this Agreement and agrees that such service shall
constitute good and sufficient service of process and notice thereof.
Nothing contained herein shall be deemed to limit in any way any right to
serve process in any manner permitted by law. Each party hereto hereby
irrevocably waives, to the fullest extent permitted by applicable law, any
and all right to trial by jury in any Proceeding arising out of or relating
to this Agreement or the transactions contemplated hereby. If either party
shall commence a Proceeding to enforce any provisions of this Agreement,
then the prevailing party in such Proceeding shall be reimbursed by the
other party for its attorney's fees and other costs and expenses incurred
with the investigation, preparation and prosecution of such Proceeding.

                  (k) Cumulative Remedies. The remedies provided herein are
                      -------------------
cumulative and not exclusive of any remedies provided by law.

                  (l) Severability. If any term, provision, covenant or
                      ------------
restriction of this Agreement is held by a court of competent jurisdiction
to be invalid, illegal, void or unenforceable, the remainder of the terms,
provisions, covenants and restrictions set forth herein shall remain in full
force and effect and shall in no way be affected, impaired or invalidated,
and the parties hereto shall use their reasonable efforts to find and employ
an alternative means to achieve the same or substantially the same result as
that contemplated by such term, provision, covenant or restriction. It is
hereby stipulated and declared to be the intention of the parties that they
would have executed the remaining terms, provisions, covenants and
restrictions without including any of such that may be hereafter declared
invalid, illegal, void or unenforceable.

                  (m) Headings. The headings in this Agreement are for
                      --------
convenience of reference only and shall not limit or otherwise affect the
meaning hereof.

                  (n) Independent Nature of Investors' Obligations and
                      ------------------------------------------------
Rights. The obligations of each Investor hereunder is several and not joint
------
with the obligations of any other Investor hereunder, and no Investor shall
be responsible in any way for the performance of the obligations of any
other Investor hereunder. The decision of each Investor to purchase
Securities pursuant to the Transaction Documents has been made independently
of any other Investor. Nothing contained herein or in any other agreement or
document delivered at any closing, and no action taken by any Investor
pursuant hereto or thereto, shall be deemed to constitute the Investors as a
partnership, an

                                    -14-

association, a joint venture or any other kind of entity, or create a
presumption that the Investors are in any way acting in concert with respect
to such obligations or the transactions contemplated by this Agreement. Each
Investor acknowledges that no other Investor has acted as agent for such
Investor in connection with making its investment hereunder. Except as
specified in the Transaction Documents, each Investor shall be entitled to
protect and enforce its rights, including without limitation the rights
arising out of this Agreement, and it shall not be necessary for any other
Investor to be joined as an additional party in any Proceeding for such
purpose.

                 [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK
                         SIGNATURE PAGES TO FOLLOW]

                                    -15-

                  IN WITNESS WHEREOF, the parties have executed this
Registration Rights Agreement as of the date first written above.

                           ZOLTEK COMPANIES, INC.

                           By:
                              ----------------------------
                              Name:
                              Title:

                 [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK
                   SIGNATURE PAGES OF INVESTORS TO FOLLOW]

                                    -16-

                  IN WITNESS WHEREOF, the parties have executed this
Registration Rights Agreement as of the date first written above.

                                   NAME OF INVESTING ENTITY

                                   --------------------------------------

                                   AUTHORIZED SIGNATORY

                                   By:
                                      -----------------------------------
                                   Name:
                                   Title:

                                   ADDRESS FOR NOTICE

                                   c/o:
                                        ---------------------------------

                                   Street:
                                           ------------------------------

                                   City/State/Zip:
                                                   ----------------------

                                   Attention:
                                              ---------------------------

                                   Tel:
                                            -----------------------------

                                   Fax:
                                            -----------------------------

                                   Email:
                                            -----------------------------

                                    -17-

                                                                       Annex A

                            Plan of Distribution

         The Selling Shareholders and any of their pledgees, donees,
transferees, assignees and successors-in-interest may, from time to time,
sell any or all of their shares of Common Stock on any stock exchange,
market or trading facility on which the shares are traded or in private
transactions. These sales may be at fixed or negotiated prices. The Selling
Shareholders may use any one or more of the following methods when selling
shares:

o    ordinary brokerage transactions and transactions in which the broker-
     dealer solicits investors;

o    block trades in which the broker-dealer will attempt to sell the shares
     as agent but may position and resell a portion of the block as
     principal to facilitate the transaction;

o    purchases by a broker-dealer as principal and resale by the broker-dealer
     for its account;

o    an exchange distribution in accordance with the rules of the applicable
     exchange;

o    privately negotiated transactions;

o    to cover short sales made after the date that this Registration Statement
     is declared effective by the Commission;

o    broker-dealers may agree with the Selling Shareholders to sell a specified
     number of such shares at a stipulated price per share;

o    a combination of any such methods of sale; and

o    any other method permitted pursuant to applicable law.

         The Selling Shareholders may also sell shares under Rule 144 under
the Securities Act, if available, rather than under this prospectus.

         Broker-dealers engaged by the Selling Shareholders may arrange for
other brokers-dealers to participate in sales. Broker-dealers may receive
commissions or discounts from the Selling Shareholders (or, if any
broker-dealer acts as agent for the purchaser of shares, from the purchaser)
in amounts to be negotiated. The Selling Shareholders do not expect these
commissions and discounts to exceed what is customary in the types of
transactions involved.

         The Selling Shareholders may from time to time pledge or grant a
security interest in some or all of the Shares owned by them and, if they
default in the performance of their secured obligations, the pledgees or
secured parties may offer and sell shares of Common Stock from time to time
under this prospectus, or under an amendment to this

                                    -18-

prospectus under Rule 424(b)(3) or other applicable provision of the
Securities Act of 1933 amending the list of selling shareholders to include
the pledgee, transferee or other successors in interest as selling
shareholders under this prospectus.

         Upon the Company being notified in writing by a Selling Shareholder
that any material arrangement has been entered into with a broker-dealer for
the sale of Common Stock through a block trade, special offering, exchange
distribution or secondary distribution or a purchase by a broker or dealer,
a supplement to this prospectus will be filed, if required, pursuant to Rule
424(b) under the Securities Act, disclosing (i) the name of each such
Selling Shareholder and of the participating broker-dealer(s), (ii) the
number of shares involved, (iii) the price at which such the shares of
Common Stock were sold, (iv)the commissions paid or discounts or concessions
allowed to such broker-dealer(s), where applicable, (v) that such
broker-dealer(s) did not conduct any investigation to verify the information
set out or incorporated by reference in this prospectus, and (vi) other
facts material to the transaction. In addition, upon the Company being
notified in writing by a Selling Shareholder that a donee or pledge intends
to sell more than 500 shares of Common Stock, a supplement to this
prospectus will be filed if then required in accordance with applicable
securities law.

         The Selling Shareholders also may transfer the shares of Common
Stock in other circumstances, in which case the transferees, pledgees or
other successors in interest will be the selling beneficial owners for
purposes of this prospectus.

         The Selling Shareholders and any broker-dealers or agents that are
involved in selling the shares may be deemed to be "underwriters" within the
meaning of the Securities Act in connection with such sales. In such event,
any commissions received by such broker-dealers or agents and any profit on
the resale of the shares purchased by them may be deemed to be underwriting
commissions or discounts under the Securities Act. Discounts, concessions,
commissions and similar selling expenses, if any, that can be attributed to
the sale of Securities will be paid by the Selling Shareholder and/or the
purchasers. Each Selling Shareholder has represented and warranted to the
Company that it acquired the securities subject to this registration
statement in the ordinary course of such Selling Shareholder's business and,
at the time of its purchase of such securities such Selling Shareholder had
no agreement or understanding, directly or indirectly, with any person to
distribute any such securities.

         The Company has advised each Selling Shareholder that it may not
use shares registered on this Registration Statement to cover short sales of
Common Stock made prior to the date on which this Registration Statement
shall have been declared effective by the Commission. If a Selling
Shareholder uses this prospectus for any sale of the Common Stock, it will
be subject to the prospectus delivery requirements of the Securities Act.
The Selling Shareholders will be responsible to comply with the applicable
provisions of the Securities Act and Exchange Act, and the rules and
regulations thereunder promulgated, including, without limitation,
Regulation M, as applicable to such Selling Shareholders in connection with
resales of their respective shares under this Registration Statement.

                                    -19-

         The Company is required to pay all fees and expenses incident to
the registration of the shares, but the Company will not receive any
proceeds from the sale of the Common Stock. The Company has agreed to
indemnify the Selling Shareholders against certain losses, claims, damages
and liabilities, including liabilities under the Securities Act.

                                    -20-

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00072-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00072-of-00352.parquet"}]]