Exhibit 4.3 


 


FORM
OF WARRANT AGENT AGREEMENT


 


THIS
WARRANT AGENT AGREEMENT (this “Agreement”) is dated [ ], 2021, between Mechanical Technology, Incorporated, a Nevada
corporation (the “Company”), and American Stock Transfer & Trust Company, LLC acting as warrant agent (the “Warrant
Agent”).


 


WHEREAS,
the Company proposes to issue common stock purchase warrants (the “Warrants”) to acquire up to ____________ shares
of common stock, par value $0.001 per share (“Common Stock”), subject to adjustment as provided herein, of the Company
(collectively, the “Warrant Shares”);


 


WHEREAS,
each Warrant shall represent the right to purchase 25% of one (1) share of Common Stock and each whole share exercisable pursuant to
the Warrants shall have an initial price of $[  ] per share (133% of the public offering price) (the “Exercise Price”),
subject to adjustment as provided hereunder; and


 


WHEREAS,
American Stock Transfer & Trust Company, LLC is willing to serve as the Warrant Agent in connection with the issuance of Warrant
Certificates (as defined below) and the other matters as provided herein.


 


NOW,
THEREFORE, in consideration of the foregoing and for the purpose of defining the terms and provisions of the Warrants and the respective
rights and obligations thereunder of the Company, the Warrant Agent and the record holders from time to time of the Warrants or, if the
Warrants are held in “street name,” a Participant (as defined below) or a designee appointed by such Participant (each, a
“Holder” and collectively, the “Holders”), the parties hereby agree as follows:


 


		1.	Definitions.
                                            For the purposes hereof, the following terms shall have the following meanings:



 


“Affiliate”
means any Person that, directly or indirectly through one or more intermediaries, controls or is controlled by or is under common control
with a Person, as such terms are used in and construed under Rule 405 under the Securities Act.


 


“Aggregate
Exercise Price” means, with respect to each exercise of Warrants held by the Holder, the Exercise Price multiplied by the aggregate
number of Warrant Shares (which must be a whole number) that such Holder intends to purchase pursuant to such exercise.


 


“Business
Day” means any day except Saturday, Sunday and any day which shall be a federal legal holiday in the United States or a day
on which banking institutions in the City of New York are authorized or required by law or other government action to close.


 


“Commission”
means the United States Securities and Exchange Commission.


 


“Common
Stock” shall have the meaning set forth in the first WHEREAS clause.


 


“Common
Stock Equivalents” means any securities of the Company or any of its subsidiaries which would entitle the holder thereof to
acquire at any time shares of Common Stock, including, without limitation, any debt, preferred shares, right, option, warrant or other
instrument that is at any time convertible into or exercisable or exchangeable for, or otherwise entitles the holder thereof to receive,
shares of Common Stock.


 


“Date
of Exercise” means the date on which the Holder shall have delivered to the Warrant Agent an appropriately completed and duly
signed Form of Election to Purchase (with the Warrant Shares Exercise Log attached to it and reference to the relevant Warrant Certificate
sufficient to identify it).


 


“Exchange
Act” means the Securities Exchange Act of 1934, as amended, and the rules and regulations of the Securities and Exchange Commission
(the “Commission”) promulgated thereunder.


 


“Exercise
Price” shall have the meaning set forth in the second WHEREAS clause.









 






     


     


    

  


“Expiration
Date” means [          ], 20261.


 


“Form
of Election to Purchase” means a Form of Election to Purchase substantially in the form attached to the Warrant.


 


“Initial
Exercise Date” means [          ], 20212.


 


“Initial
Issuance Date” means [          ], 2021.


 


“Person”
means a corporation, association, partnership, limited liability corporation, organization, business, individual, trust, government or
political subdivision thereof or governmental agency.


 


“Prospectus”
means the final prospectus relating to the Warrant Shares included in the Registration Statement.


 


“Registration
Statement” means, collectively, the various parts of the registration statement prepared by the Company on Form S-1 (File No.
333-54064) with respect to the Warrant Shares, each as amended as of the date hereof, including the Prospectus therein and all exhibits
filed with such registration statement.


 


“Securities
Act” means the Securities Act of 1933, as amended.


 


“Specified
Merger” has the meaning set forth in subsection 9(d).


 


“Trading
Day” means (i) a day on which the shares of Common Stock are traded on the Trading Market on which the shares of Common Stock
are then listed or quoted, or (ii) if the shares of Common Stock are not listed on any such Trading Market, a day on which the shares
of Common Stock are traded in the over-the-counter market, as reported by the OTC Markets; provided, that in the event that the shares
of Common Stock are not listed or quoted as set forth in clause (i) or (ii) hereof, then Trading Day shall mean a Business Day.


 


“Trading
Market” means the New York Stock Exchange, the NYSE American, the Nasdaq Capital Market, the Nasdaq Global Market or the Nasdaq
Global Select Market.


 


“VWAP”
means, for any date, the price determined by the first of the following clauses that applies: (a) if the Common Stock is then listed
or quoted on a Trading Market, the daily volume weighted average price of the Common Stock for such date (or the nearest preceding date)
on the Trading Market on which the Common Stock is then listed or quoted as reported by Bloomberg L.P. (based on a Trading Day from 9:30
a.m. (New York City time) to 4:02 p.m. (New York City time)), (b) if OTCQB or OTCQX is the principal market on which the Common Stock
is traded, the volume weighted average price of the Common Stock for such date (or the nearest preceding date) on OTCQB or OTCQX as applicable,
(c) if the Common Stock is not then listed or quoted for trading on OTCQB or OTCQX and if prices for the Common Stock are then reported
on the OTC (“Pink”) Markets (or a similar organization or agency succeeding to its functions of reporting prices), the most
recent bid price per share of the Common Stock so reported, or (d) in all other cases, the fair market value of a share of Common Stock
as determined by an independent appraiser selected in good faith by the holders of a majority in interest of the Warrants then outstanding
and reasonably acceptable to the Company, the fees and expenses of which shall be paid by the Company.


 


“Warrant
Certificate” means a certificate in substantially the form attached hereto as Exhibit A representing such
number of Warrants set forth on the Warrant Certificate.


 


“Warrants”
shall have the meaning set forth in the first WHEREAS clause.


 


“Warrant
Shares” shall have the meaning set forth in the first WHEREAS clause.


 



 


 



1
Five years after the Initial Issuance Date.


2
Same date as Initial Issuance Date.




 






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2. Form
of Warrant.


 





(a) Warrants
in Global Form. The Warrants shall initially be issuable in book-entry registration only and evidenced by one or more global Warrant
Certificates (the “Global Warrant Certificates”) deposited with the Depository Trust Company (the “Depository”)
and registered in the name of Cede & Co. (“Cede”), a nominee of the Depository. Ownership of beneficial interests
in the Warrants shall be shown on, and the transfer of such ownership shall be effected through, records maintained by (i) the Depository
or its nominee for each Global Warrant Certificate or (ii) institutions that have accounts with the Depository (such institutions, with
respect to a Warrant in its account, each a “Participant”). For purposes of this Agreement, the delivery of a notice
from the Depository or a Participant of the transfer or exercise of Warrants in the form of a Global Warrant Certificate shall be deemed
to constitute the delivery of a Warrant Certificate with respect to such transfer or exercise. If the Depository subsequently ceases
to make its book-entry settlement system available for the Warrants, the Company may instruct the Warrant Agent regarding other arrangements
for book-entry settlement. If the Company determines, in its sole discretion, not to have securities represented by the Global Warrant
Certificates, the Company will instruct the Warrant Agent to prepare and deliver physical certificates evidencing the Warrants in exchange
for the beneficial interests in the Global Warrant Certificates, based on directions received by the Depository from its Participants
with respect to ownership of beneficial interests in the Global Warrant Certificates. In such event, any physical certificates evidencing
the Warrants shall represent one or more Warrants as set forth on the Warrant Certificate and be issued in registered form only as definitive
Warrant Certificates and shall be substantially in the form attached hereto as Exhibit A, shall be dated the date of issuance
thereof (whether upon initial issuance, register of transfer, exchange or replacement) and shall bear such legends and endorsements typed,
stamped, printed, lithographed or engraved thereon as the Company may deem appropriate and as are not inconsistent with the provisions
of this Agreement.


  


(b) Effect
of Signature. Warrant Certificates shall be signed by, or bear the facsimile or electronic signature of, the chief executive officer,
president, chairperson of the board, chief financial officer, treasurer, any vice president, or secretary of the Company. In the event
the person whose facsimile or electronic signature has been placed upon any Warrant Certificate shall have ceased to serve in the capacity
in which such person signed the Warrant Certificate before such Warrant Certificate is issued, it may be issued with the same effect
as if he or she had not ceased to be such at the date of issuance.


 


(c) Effect
of Countersignature. Unless and until countersigned by the Warrant Agent pursuant to this Agreement, a Warrant Certificate shall
be invalid and of no effect and may not be exercised by the holder thereof. Such signature by the Warrant Agent upon any Warrant Certificate
executed by the Company shall be conclusive evidence that such Warrant Certificate has been duly issued under the terms of this Agreement.


 


(d) Warrant
Register. The Warrant Agent shall maintain books (the “Warrant Register”), for the registration of original issuance
and the registration of transfer of the Warrants. Upon the initial issuance of the Warrants, the Warrant Agent shall issue and register
the Warrants in the names of the respective holders thereof in such denominations and otherwise in accordance with instructions delivered
to the Warrant Agent by or on behalf of the Company. The Company and the Warrant Agent may deem and treat the registered Holder of each
Warrant Certificate as the absolute owner of the Warrants represented thereby for the purpose of any exercise thereof or any distribution
to the Holder, and for all other purposes, absent actual notice to the contrary. Any Person in whose name ownership of a beneficial interest
in the Warrants evidenced by a Global Warrant Certificate is recorded in the records maintained by the Depository or its nominee shall
be deemed the “beneficial owner” thereof; provided, that all such beneficial interests shall be held through a Participant,
which shall be the registered holder of such Warrants.


 


(e) Registration
of Transfers. The Warrant Agent shall register the transfer of any portion of a Warrant Certificate in the Warrant Register,
upon surrender of the Warrant Certificate, with the Form of Assignment attached thereto, to the Warrant Agent at its address
specified for notice set forth in Section 14 below. Upon any such registration or transfer, a new Warrant Certificate substantially
in the form attached hereto as Exhibit A (any such new Warrant Certificate, a “New Warrant
Certificate”), evidencing the portion of the Warrant Certificate so transferred shall be issued to the transferee and a
New Warrant Certificate evidencing the remaining portion of the Warrant Certificate not so transferred, if any, shall be issued to
the transferring Holder. Upon issuance and delivery of the New Warrant Certificate, the Warrant Certificate surrendered to the
Warrant Agent shall be clearly marked “cancelled” or bear a similar statement to that effect. The delivery of the New
Warrant Certificate by the Warrant Agent to the transferee thereof shall be deemed to constitute acceptance by such transferee of
all of the rights and obligations of a holder of a Warrant Certificate. Notwithstanding the foregoing, so long as the Warrants are
evidenced by Global Warrant Certificates deposited with the Depository, ownership of beneficial interests in the Warrants shall be
shown on, and the transfer of such ownership shall be effected through, records maintained (i) by the Depository or its nominee for
each Warrant; (ii) by Participants; or (iii) directly on the book-entry records of the Warrant Agent with respect only to owners of
beneficial interests that represent such direct registration.


 










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(f) Warrants
in Uncertificated Form. Notwithstanding the foregoing and anything else herein to the contrary, the Warrants may be issued in uncertificated
form if so specified by the Company.


 


3. Term
of Warrants. Warrants shall be exercisable by the registered Holder at any time and from time to time on or after the Initial Exercise
Date until 5:00 p.m. (New York time) on the Expiration Date. At 5:00 p.m. (New York time) on the Expiration Date, any Warrant not exercised
prior thereto (including without limitation, by payment of the applicable Aggregate Exercise Price on or prior to 5:00 p.m. (New York
time) on the Expiration Date) shall be and become void and of no value.


 


4. Exercise
of Warrants and Delivery of Warrant Shares.


 


(a) Exercise
Procedure. At such times, and upon such representations and agreements, upon delivery of an appropriately completed and duly signed
Form of Election to Purchase (with the Warrant Shares Exercise Log attached and reference to the applicable Warrant Certificate sufficient
to identify it) to the Warrant Agent (or, in the case of a Global Warrant Certificate, properly delivered by the Participant in accordance
with the Depository’s procedures), at its address for notice set forth in Section 14, and payment of the Aggregate Exercise Price
by the date that is one (1) Trading Day after the Date of Exercise, the Company shall, on or prior to the date that is the later of (A)
the date that is three (3) Trading Days after the Date of Exercise and (B) the date that is two (2) Trading Days after the date on which
the Aggregate Exercise Price has been paid in accordance with Section 10 below (such later date, the “Warrant Share Delivery
Date”), (i) provided that the Company’s transfer agent (the “Transfer Agent”) is participating in
the Depository’s Fast Automated Securities Transfer Program and an effective registration statement is available for the issuance
of the Warrant Shares, or (ii) if the Transfer Agent is not participating in the Depository’s Fast Automated Securities Transfer
Program, issue and dispatch by overnight courier to the address as specified in the Form of Election to Purchase, a certificate, registered
in the Company’s share register in the name of the Holder or its designee, for the number of shares of Common Stock to which the
Holder is entitled pursuant to such exercise. Any Person so designated by the Holder to receive Warrant Shares shall be deemed to have
become holder of record of such Warrant Shares as of the time that the Holder shall have delivered to the Warrant Agent an appropriately
completed and duly signed Form of Election to Purchase (with the Warrant Shares Exercise Log attached to it and reference to the relevant
Warrant Certificate sufficient to identify it), provided that the Holder delivers the Aggregate Exercise Price by the date that is one
(1) Trading Day after the Date of Exercise.


 


(b)
If the Holder delivers a Form of Election to Purchase but fails, within one Trading Day after the Date of Exercise, to deliver the Aggregate
Exercise Price, then the Holder shall only be deemed to be the holder of record of the Warrant Shares upon delivery of the Aggregate
Exercise Price, so long as such Aggregate Exercise Price is delivered within three (3) Trading Days of the Date of Exercise.


 


(c)
No ink-original Form of Election to Purchase shall be required, nor shall any medallion guarantee (or other type of guarantee or notarization)
of any Form of Election to Purchase be required. Notwithstanding anything herein to the contrary, the Holder shall not be required to
physically surrender any Warrant Certificate to the Company or Warrant Agent until all of the Warrant Shares issuable thereunder have
been purchased and all of the Warrants evidenced by such Warrant Certificate have been exercised in full, in which case, the Holder shall
surrender such Warrant Certificate to the Company or Warrant Agent for cancellation within five (5) Trading Days of the date the final
Form of Election to Purchase is delivered to the Warrant Agent. Partial exercises of such Warrant Certificate resulting in purchases
of a portion of the total number of Warrant Shares available thereunder shall have the effect of lowering the outstanding number of Warrant
Shares purchasable thereunder in an amount equal to the applicable number of Warrant Shares purchased. The Holder and any assignee,
by acceptance of a Warrant Certificate, acknowledge and agree that, by reason of the provisions of this subsection, following a partial
exercise of such Warrant Certificate, the number of Warrant Shares issuable upon exercise of such Warrant Certificate at any given time
may be less than the amount stated on the face thereof.


 







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(d)
If fewer than all Warrant Shares issuable upon exercise of the relevant Warrant Certificate are purchased upon any exercise thereof,
then promptly following the date on which the Holder has taken all actions necessary under the terms of this Agreement for such Holder
to receive Warrant Shares and be deemed to have become the holder of record of such Warrant Shares and at the request of the Holder (provided
that the Holder has delivered the original physical Warrant Certificate to the Warrant Agent for cancellation), the Company will execute
and deliver to the Holder or its assigns a New Warrant Certificate (dated the date such Holder is deemed to have become the holder of
record of such Warrant Shares) evidencing the unexercised portion of the relevant Warrant Certificate. If fewer than all the Warrants
evidenced by a Global Warrant Certificate are exercised, a notation shall be made to the records maintained by the Depository, its nominee
for each Global Warrant Certificate, or a Participant, as appropriate, evidencing the balance of the Warrants remaining after such exercise.


 


(e)
In addition to any other rights available to the Holder, if the Holder has taken all actions necessary under the terms of this Agreement
for such Holder to receive Warrant Shares subject to a Form of Election to Purchase on a Warrant Share Delivery Date and the Company
fails, or fails to cause the Warrant Agent, to transmit to the Holder the Warrant Shares in accordance with the provisions of subsection
4(a) above on or before the applicable Warrant Share Delivery Date, and if after such date the Holder is required by its broker to purchase
(in an open market transaction or otherwise) or the Holder’s brokerage firm otherwise purchases, 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 (A) pay in cash to the Holder the amount, if any, 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 (1) the number
of Warrant Shares that the Company was required to deliver to the Holder in connection with the exercise at issue times (2) the price
at which the sell order giving rise to such purchase obligation was executed, and (B) 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 (in which case such exercise shall
be deemed rescinded) 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. For example, if the Holder purchases shares of Common Stock having a total
purchase price of $11,000 to cover a Buy-In with respect to an attempted exercise of shares of Common Stock with an aggregate sale price
giving rise to such purchase obligation of $10,000, under clause (A) of the immediately preceding sentence the Company shall be required
to pay the Holder $1,000. The Holder shall provide the Company written notice indicating the amounts payable to the Holder in respect
of a Buy-In and evidence of the amount of such loss.


 


(f)
If at the time of exercise hereof there is no effective registration statement registering, or the prospectus contained therein is not
available for the issuance of the Warrant Shares to the Holder, then this Warrant may also be converted, in whole or in part, into Common
Stock at such time by means of a “cashless exercise” in which the Holder shall be entitled to receive a number of Warrant
Shares equal to the quotient obtained by dividing [(A-B) (X)] by (A), where:


 


(A)
= as applicable: (i) the VWAP on the Trading Day immediately preceding the date of the applicable Form of Election to Purchase if such
Form of Election to Purchase is both executed and delivered pursuant to Section 4(a).


 


(B)
= the Exercise Price of this Warrant, as then in effect; and


 


(X)
= the number of Warrant Shares that would be issuable upon exercise of this Warrant in accordance with the terms of this Warrant if such
exercise were by means of a cash exercise rather than a cashless exercise.


 


The
Holder will deliver the Form of Election to Purchase to the Company for confirmation of the above formula. The Company will promptly
notify the Warrant Agent with authorization to issue the Warrant Shares and debit the Warrant.


 


If
Warrant Shares are issued in such a cashless exercise, which is an exchange of the warrants for the Warrant Shares, the parties acknowledge
and agree that in accordance with Section 3(a)(9) of the Securities Act, the Warrant Shares shall take on the characteristics of the
Warrants being exercised. The Company agrees not to take any position contrary to this Section 4(f).


 










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5.
Holder’s Exercise Limitations. A Holder shall not have the right to exercise any portion of such Holder’s Warrants,
to the extent that after giving effect to such issuance after exercise, the Holder (together with the Holder’s Affiliates, and
any other Persons acting as a group together with the Holder or any of the Holder’s Affiliates (such Persons, “Attribution
Parties”)), would beneficially own in excess of the Beneficial Ownership Limitation (as defined below). For purposes of the
foregoing sentence, the number of shares of Common Stock beneficially owned by the Holder and its Affiliates and Attribution Parties
shall include the number of shares of Common Stock issuable upon exercise of a Holder’s Warrants with respect to which such determination
is being made, but shall exclude the number of shares of Common Stock which would be issuable upon (i) exercise of the remaining, nonexercised
portion of such Holder’s Warrants beneficially owned by such Holder or any of its Affiliates or Attribution Parties and (ii) exercise
or conversion of the unexercised or nonconverted portion of any other securities of the Company (including, without limitation, any other
Common Stock Equivalents) subject to a limitation on conversion or exercise analogous to the limitation contained herein beneficially
owned by such Holder or any of its Affiliates or Attribution Parties. Except as set forth in the preceding sentence, for purposes of
this Section 5, beneficial ownership shall be calculated in accordance with Section 13(d) of the Exchange Act and the rules and regulations
promulgated thereunder, it being acknowledged by each Holder that the Company is not representing to such Holder that such calculation
is in compliance with Section 13(d) of the Exchange Act and such Holder is solely responsible for any schedules required to be filed
in accordance therewith. To the extent that the limitation contained in this Section 5 applies, the determination of whether a Holder’s
Warrants are exercisable (in relation to other securities owned by such Holder together with any Affiliates and Attribution Parties)
and of which portion of such Holder’s Warrants are exercisable shall be in the sole discretion of such Holder, and any exercise
of Warrants by such Holder shall be deemed to be the Holder’s determination of whether such Warrants are exercisable (in relation
to other securities owned by such Holder together with any Affiliates and Attribution Parties) and of which Warrants are exercisable,
in each case subject to the Beneficial Ownership Limitation, and neither the Company nor the Warrant Agent shall have any obligation
to verify or confirm the accuracy of such determination. In addition, a determination as to any group status as contemplated above shall
be determined in accordance with Section 13(d) of the Exchange Act and the rules and regulations promulgated thereunder. For purposes
of this Section 5, in determining the number of outstanding shares of Common Stock, a Holder may rely on the number of outstanding shares
of Common Stock as reflected in (A) the Company’s most recent periodic or annual report filed with the Commission, as the case
may be, (B) a more recent public announcement by the Company or (C) a more recent written notice by the Company or the Transfer Agent
setting forth the number of shares of Common Stock outstanding. Upon the written or oral request of a Holder, the Company shall within
one Trading Day confirm orally and in writing to the Holder the number of Common Shares then outstanding. In any case, the number of
outstanding share of Common Stock shall be determined after giving effect to the conversion or exercise of securities of the Company,
including a Holder’s Warrant, by the Holder or its Affiliates or Attribution Parties since the date as of which such number of
outstanding shares of Common Stock was reported. The “Beneficial Ownership Limitation” shall be 4.99% (or, upon election
by a Holder prior to the issuance of any Warrants, 9.99%) of the number of shares of Common Stock outstanding immediately after giving
effect to the issuance of the shares of Common Stock issuable upon exercise of such Holder’s Warrants. The Holder, upon notice
to the Company and the Warrant Agent, may increase or decrease the Beneficial Ownership Limitation provisions of this Section 5, provided
that the Beneficial Ownership Limitation in no event exceeds 9.99% of the number of shares of Common Stock outstanding immediately after
giving effect to the issuance of shares of Common Stock upon exercise of the Warrants held by the Holder and the provisions of this Section
5 shall continue to apply. Any increase in the Beneficial Ownership Limitation will not be effective until the 61st day
after such notice is delivered to the Company and the Warrant Agent. The provisions of this paragraph shall be construed and implemented
in a manner otherwise than in strict conformity with the terms of this Section 5 to correct this paragraph (or any portion hereof) which
may be defective or inconsistent with the intended Beneficial Ownership Limitation herein contained or to make changes or supplements
necessary or desirable to properly give effect to such limitation. The limitations contained in this paragraph shall apply to a successor
holder Warrants.


 


6. Charges,
Taxes and Expenses. Issuance and delivery of certificates for Warrant Shares shall be made without charge to the Holder for any
issue or transfer tax, or transfer agent fee in respect of the issuance of such certificates, all of which taxes shall be paid by
the Company; provided, however, that the Company shall not be obligated 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 liabilities that may arise as a result of holding or transferring any Warrant
Certificate. The Company shall pay all Warrant Agent and Transfer Agent fees required for same-day processing of any
Form of Election to Purchase and all fees to the Depository (or another established clearing corporation performing similar
functions) required for same-day electronic delivery of the Warrant Shares.


 










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7. Replacement
of Warrant Certificate. If any Warrant Certificate is mutilated, lost, stolen or destroyed, the Company shall issue or cause to be
issued in exchange and substitution for and upon cancellation thereof, or in lieu of and substitution for such Warrant Certificate, a
New Warrant Certificate, but only upon receipt of evidence reasonably satisfactory to the Company of such loss, theft or destruction
and customary and reasonable indemnity, if requested. Applicants for a New Warrant Certificate under such circumstances shall also comply
with such other reasonable regulations and procedures and pay such other reasonable third-party costs as the Company may prescribe.


 


8. Reservation
of Warrant Shares. The Company covenants that it will at all times reserve and keep available out of its authorized but unissued
and otherwise unreserved Common Stock, solely for the purpose of enabling it to issue Warrant Shares upon exercise of all outstanding
Warrants as herein provided, the number of Warrant Shares which are then issuable and deliverable upon the exercise of all outstanding
Warrants (taking into account any adjustments pursuant to Section 9 below). 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 and issued, and be fully paid and non-assessable.


 


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


 


(a) Stock
Dividends and Splits. If the Company, (i) pays a dividend or distribution in the form of shares of its Common Stock on its Common
Stock, (ii) subdivides outstanding shares of Common Stock into a greater number of shares or otherwise effects a stock split, or (iii)
combines outstanding shares of Common Stock into a lesser number of shares or otherwise effects a reverse split, 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 subsection 9(a) shall become effective immediately after the record date
for the determination of stockholders 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.


 


(b) Number
of Warrant Shares. Simultaneously with any adjustment to the Exercise Price pursuant to subsection 9(a) above, the number of Warrant
Shares that may be purchased upon exercise of each Warrant shall be increased or decreased proportionately, as the case may be, 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.


 


(c) Certain
Extraordinary Transactions. Except as provided in Section 9(d), in case of any consolidation or merger of the Company into another
corporation (other than a merger in which the Company is the continuing corporation) or in case of any sale, lease or conveyance to another
corporation of our property as an entirety in which the proceeds of the transaction are distributed to the Company’s stockholders,
the Company shall, as a condition precedent to such transaction, cause effective provisions to be made so that the holder of the Warrants
shall have the right thereafter by exercising the Warrant, to purchase the kind and amount of shares of stock and other securities and
property receivable upon such consolidation, merger, sale or conveyance by a holder of the number of shares of Common Stock which might
have been purchased upon exercise of the warrant immediately prior to such consolidation, merger, sale or conveyance. Any such provision
shall include provision for adjustments which shall be as nearly equivalent as may be practicable to the adjustments provided for in
the warrant.


 










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(d) Specified
Merger. Notwithstanding the provisions of subsection 9(c) of this Agreement, in the event of a Specified Merger, as hereinafter
defined, the Warrants, if not exercised prior to the effective time of the Specified Merger, shall, at the effective time of the
Specified Merger, without any action on the part of the Holder, become and be converted into the right to receive cash or securities
equal to the amount determined by multiplying the number of Warrant Shares issuable upon exercise of the Warrant by the amount by
which (x) the consideration payable with respect to one share of Common Stock in the Specified Merger exceeds (y) the Exercise
Price. A “Specified Merger” shall mean the merger or consolidation of the Company into another corporation or
entity or the sale by the Company of all or substantially all of its business and assets in a transaction in which the net proceeds
or other consideration from such sale are distributed to the Company’s stockholders in liquidation of their shares of Common
Stock, if, and only if, the sole consideration to be received by the holders of the Common Stock is cash, including any contingent
cash, and/or securities all of which are listed on a Trading Market or another United States, Canadian or foreign stock exchange or
market designated by the Company’s board of directors and the shares are issuable pursuant to a registration statement on Form
S-4 or other applicable form of registration statement. Securities issued in the Specified Merger shall be valued at the average
closing price thereof on the Trading Market or such other stock exchange or market on which the securities are listed or traded on
the Trading Day immediately prior to the effective date of the Specified Merger unless the agreement relating to the Specified
Merger provides another method of determining the value thereof, in which event the valuation determined by such agreement shall
prevail. Payment to the holder of this Warrant with respect to any such securities shall be payable in either cash or in such
securities (valued as herein provided), in the same manner as cash or securities is being paid or issued to the holders of the
Common Stock. If, in a Specified Merger, the value of the consideration payable with respect to one share of Common Stock is equal
to or less than the Exercise Price, no payment shall be made to the Holder of the Warrants, and the Warrants shall expire and cease
to be exercisable. The Company shall give the Holders and the Warrant Agent reasonable notice of a proposed effective date of a
Specified Merger.


  


(e) Notice
of Adjustments. Upon the occurrence of each adjustment pursuant to this Section 9, the Company at its expense will promptly calculate
such adjustment in accordance with the terms of this Agreement and prepare a certificate setting forth such adjustment, including a statement
of the adjusted Exercise Price and adjusted number of Warrant Shares or type of consideration issuable upon exercise of each Warrant
(as applicable), describing the transactions giving rise to such adjustments and showing in detail the facts upon which such adjustment
is based. The Company will reasonably promptly deliver or cause to be delivered to each Holder who makes a request in writing and to
the Warrant Agent, a copy of each such certificate.


 


(f) 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 (other than a dividend payable solely in shares of Common Stock) or (ii) authorizes the voluntary dissolution, liquidation
or winding up of the affairs of the Company, or (iii) proposed a transaction involving a merger, consolidation, sale of assets or similar
transaction, including a proposed Specified Merger, then the Company shall deliver or cause to be delivered to each Holder a notice describing
the material terms and conditions of such dividend, distribution or transaction. Notwithstanding anything to the contrary in this subsection
9(f), the failure to deliver any notice under this subsection 9(f) or any defect therein shall not affect the validity of the corporate
action required to be described in such notice. Until the exercise of a Holder’s Warrant or any portion of such Warrant, a Holder
shall not have nor exercise any rights by virtue of ownership of a Warrant as a stockholder of the Company (including without limitation
the right to notification of stockholder meetings or the right to receive any notice or other communication concerning the business and
affairs of the Company other than as provided in this subsection 9(f)), except as expressly set forth in this Section 9.


 


(g) Notices
to Holders on Registration Statement. If, at any time while any Warrants remain outstanding, the Registration Statement (or any subsequent
registration statement registering the sale or resale of the Warrant Shares) is not effective or is not otherwise available for the sale
of the Warrant Shares, the Company shall deliver notice to the record Holders that such registration statement is not then effective
for the sale of Warrant Shares and shall deliver notice to the record Holders if and when the registration statement is effective again
and available for the sale of the Warrant Shares (it being understood and agreed that the foregoing shall not limit the ability of any
holder thereof to sell any of the Warrant Shares in compliance with applicable federal and state securities laws). The Company shall
use its commercially reasonable best efforts to maintain a current and effective registration statement relating to the Warrant Shares
until the expiration of the Warrants.


 


(h)
To the extent that any notice provided to the Holders under this Agreement constitutes, or contains, material, non-public information
regarding the Company or any of the Company’s subsidiaries, the Company shall simultaneously file such notice with the Commission
on a Current Report on Form 8-K.


 










     8


     


    

  



 


10. Payment
of Exercise Price. The Holder shall pay the Aggregate Exercise Price by paying, in lawful money of the United States, by
certified check payable to the Warrant Agent, as agent for the Company, or bank draft payable to the order of the Company or by wire
transfer of immediately available funds to an account designated in writing by the Company (or as otherwise agreed to by the
Company) delivered to the Warrant Agent not later than one Trading Day after the Date of Exercise. Notwithstanding the foregoing, if
payment is made in any form other than a wire transfer of immediately available funds, neither the Warrant Agent nor the Company
shall be required to issue Warrant Shares until the Warrant Agent’s bank shall have confirmed that the payment has cleared,
which date shall be the date that the Holder has made payment of the Exercise Price.


 


11. Holder
Not Deemed a Stockholder. The Holder, solely in such Person’s capacity as a Holder, shall not be entitled to vote or receive
dividends or be deemed the holder of shares of the Company for any purpose, nor shall anything contained in the Warrants be construed
to confer upon the Holder, solely in such Person’s capacity as a Holder of Warrants, any of the rights of a stockholder of the
Company or any right to vote, give or withhold consent to any corporate action (whether any reorganization, issue of stock, reclassification
of stock, consolidation, merger, conveyance or otherwise), receive notice of meetings, receive dividends or subscription rights, or otherwise,
prior to the issuance to the Holder of the Warrant Shares which such Person is then entitled to receive upon the due exercise of the
Warrants, except as expressly set forth in Section 9.


 


12. No
Fractional Shares. No fractional shares will be issued in connection with any exercise of a 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 Exercise Price.


 


13. Exchange
Act Filings. The Holder agrees and acknowledges that it shall have sole responsibility for making any applicable filings with the
U.S. Securities and Exchange Commission pursuant to Sections 13 and 16 of the Exchange Act as a result of its acquisition of any Warrant
and the Warrant Shares and any future retention or transfer thereof.


 


14. Notices.
Any and all notices or other communications or deliveries hereunder (including without limitation any Form of Election to Purchase) shall
be in writing and shall be deemed given and effective on the earliest of (a) the date of transmission, if such notice or communication
is delivered via facsimile at the facsimile number or by PDF sent by email specified in this Section 14 prior to 5:00 p.m. (New York
time) on a Business Day, (b) the next Business Day after the date of transmission, if such notice or communication is delivered via facsimile
at the facsimile number or by PDF send by email as specified in this Section 14 on a day that is not a Business Day or later than 5:00
p.m. (New York time) on any Business Day, (c) the Business Day following the date of mailing, if sent by nationally recognized overnight
courier service which provides evidence of delivery, or (d) upon actual receipt by the party to whom such notice is required to be given.
The addresses for such communications shall be:


 


if
to the Company:


 


Mechanical
Technology, Incorporated 


325
Washington Avenue Extension

Albany, NY 12206

(518) 218-2550


Attn:
   Michael Toporek 


Email:
  MToporek@mtiinstruments.com


 


if
to the Warrant Agent:


 


American
Stock Transfer & Trust Company, LLC


6201
15th Avenue


Brooklyn,
NY 11219


Attention:
Reorg Department


 


Email: Reorg_warrants@astfinancial.com



 

if
to the Holder:


 


to
the address or facsimile number or email 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.


 










     9


     


    

   


15. Warrant
Agent.


 


(a)
The Company and the Warrant Agent hereby agree that the Warrant Agent will serve as an agent of the Company as set forth in this Agreement.


 


(b)
The Warrant Agent shall not by any act hereunder be deemed to make any representation as to validity or authorization of the Warrants
or the Warrant Certificates (except as to its countersignature thereon) or of any securities or other property delivered upon exercise
of any Warrant, or as to the number or kind or amount of securities or other property deliverable upon exercise of any Warrant or the
correctness of the representations of the Company made in such certificates that the Warrant Agent receives.


 


(c)
The Warrant Agent shall not have any duty to calculate any cashless exercises or determine any required adjustments with respect to the
Exercise Price or the kind and amount of securities or other property receivable by Holders upon the exercise of Warrants, nor to determine
the accuracy or correctness of any such calculation.


 


(d)
The Warrant Agent shall not (i) be liable for any recital or statement of fact contained herein or in the Warrant Certificates or for
any action taken, suffered or omitted by it in good faith in the belief that any Warrant Certificate or any other document or any signature
is genuine or properly authorized, (ii) be responsible for any failure by the Company to comply with any of its obligations contained
in this Agreement or in the Warrant Certificates, (iii) be liable for any act or omission in connection with this Agreement except for
its own gross negligence or willful misconduct or (iv) have any responsibility to determine whether a transfer of a Warrant complies
with applicable securities laws.


 


(e)
The Warrant Agent is hereby authorized to accept instructions with respect to the performance of its duties hereunder solely on behalf
of the Company from the Chief Executive Officer, the President, the Chief Financial Officer, or the Secretary or any Assistant Secretary
of the Company and to apply to any such officer for written instructions (which will then be reasonably promptly given) and the Warrant
Agent shall not be liable for any action taken or suffered to be taken by it in good faith in accordance with the instructions of any
such officer, except for its own gross negligence or willful misconduct, but in its discretion the Warrant Agent may in lieu thereof
accept other evidence of such or may require such further or additional evidence as it may deem reasonable.


 


(f)
The Warrant Agent may exercise any of the rights and powers hereby vested in it or perform any duty hereunder either itself or by or
through its attorneys, agents or employees, provided reasonable care has been exercised in the selection and in the continued employment
of any persons. The Warrant Agent shall not be under any obligation or duty to institute, appear in or defend any action, suit or legal
proceeding in respect hereof, unless first indemnified to its satisfaction. The Warrant Agent shall promptly notify the Company in writing
of any claim made or action, suit or proceeding instituted against or arising out of or in connection with this Agreement.


 


(g)
The Company will take such action as may reasonably be required by the Warrant Agent in order to enable it to carry out or perform its
duties under this Agreement.


 


(h)
The Warrant Agent shall act solely as agent of the Company hereunder. The Warrant Agent shall only be obligated to perform such duties
as are specifically set forth herein.


 


(i)
The Warrant Agent may, at its own expense, consult with legal counsel satisfactory to it (who may be legal counsel for the Company),
and the Warrant Agent shall incur no liability or responsibility to the Company or to any Holder for any action taken, suffered or omitted
by it in good faith in accordance with the opinion or advice of such counsel.


 


(j)
The Company agrees to pay to the Warrant Agent compensation for all services rendered by the Warrant Agent hereunder as the Company and
the Warrant Agent may agree from time to time, and to reimburse the Warrant Agent for reasonable expenses incurred in connection with
the execution and administration of this Agreement (including the reasonable compensation and expenses of its counsel), and further agrees
to indemnify the Warrant Agent for, and hold it harmless against, any loss, liability or expense incurred without gross negligence, bad
faith or willful misconduct on its part, arising out of or in connection with the acceptance and administration of this Agreement.


 










     10


     


    




 


(k)
No resignation or removal of the Warrant Agent and no appointment of a successor warrant agent shall become effective until the acceptance
of appointment by the successor warrant agent as provided herein. The Warrant Agent may resign its duties and be discharged from all
further duties and liability hereunder (except liability arising as a result of the Warrant Agent’s own gross negligence, bad faith
or willful misconduct) after giving 60 days prior written notice to the Company. The Company may remove the Warrant Agent upon written
notice, and the Warrant Agent shall thereupon in like manner be discharged from all further duties and liabilities hereunder, except
as aforesaid. Upon such resignation or removal, the Company shall appoint in writing a new warrant agent. If the Company fails to do
so within a period of 30 days after it has been notified in writing of such resignation by the resigning Warrant Agent or after such
removal, then the resigning Warrant Agent or the Holder of any Warrant (if such Holder first submits his, her or its Warrant Certificate
for inspection by the Company) may apply to any court of competent jurisdiction for the appointment of a new warrant agent, provided
that, for purposes of this Agreement, the Company shall be deemed to be the Warrant Agent until a new warrant agent is appointed. After
acceptance in writing of such appointment by the new warrant agent, it shall be vested with the same powers, rights, duties and responsibilities
as if it had been originally named herein as the Warrant Agent. Not later than the effective date of any such appointment, the Company
shall give notice thereof to the resigning or removed Warrant Agent. Failure to give any notice provided for in this subsection 15(k),
however, or any defect therein, shall not affect the legality or validity of the resignation of the Warrant Agent or the appointment
of a new warrant agent, as the case may be. The Company shall, or shall cause the successor Warrant Agent to, deliver to each Holder
at such Holder’s last address as shown on the register of Holders maintained by the Warrant Agent, notice of the appointment of
the successor Warrant Agent and such successor Warrant Agent’s address for communication.


 


(l)
Any corporation into which the Warrant Agent or any new warrant agent may be merged or converted or any corporation resulting from any
consolidation to which the Warrant Agent or any new warrant agent shall be a party or any corporation to which the Warrant Agent transfers
substantially all of its corporate trust business shall be a successor Warrant Agent under this Agreement without any further act, provided
that such corporation (i) would be eligible for appointment as successor to the Warrant Agent under the provisions of subsection 15(k)
above or (ii) is a wholly owned subsidiary of the Warrant Agent. 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 each Holder in accordance with Section 14 above.


 


16. Miscellaneous.


 


(a) Successors
and Assigns. This Agreement shall be binding on and inure to the benefit of the Company, the Warrant Agent and the Holders, and their
respective successors and assigns. Subject to the preceding sentence, nothing in this Agreement shall be construed to give to any Person
other than the Company, the Warrant Agent and the Holders any legal or equitable right, remedy or cause of action under this Agreement.


 


(b) Amendments
and Waivers. The Company may, without the consent of the Holders, by supplemental agreement or otherwise, add to the covenants and
agreements of the Company for the benefit of the Holders, or surrender any rights or power reserved to or conferred upon the Company
in this Agreement, provided that such changes or corrections shall not adversely affect the interests of Holders of then outstanding
Warrants in any respect. The Company may, with the consent, in writing or at a meeting, of the Holders of outstanding Warrants exercisable
for a majority of the Warrant Shares, amend in any way, by supplemental agreement or otherwise, this Agreement and/or all of the outstanding
Warrant Certificates; provided, however, that no such amendment shall adversely affect any Warrant differently than it affects all other
Warrants, unless the Holder thereof consents thereto. The Warrant Agent shall, at the request of the Company, and without need of independent
inquiry as to whether such supplemental agreement is permitted by the terms of this Section 16(b), join with the Company in the execution
and delivery of any such supplemental agreements, but shall not be required to join in such execution and delivery for such supplemental
agreement to become effective.


 


(c) Choice
of Law, etc. 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 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 Agreement or the transactions
contemplated hereby. If either party shall commence an action or proceeding to enforce any provisions of this Agreement, then the
prevailing party in such action or proceeding shall be reimbursed by the other party for its attorneys’ fees and other costs
and expenses incurred with the investigation, preparation and prosecution of such action or proceeding.


 










     11


     


    

   


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


 


(e) Severability.
In case any one or more of the provisions of this Agreement shall be invalid or unenforceable in any respect, the validity and enforceability
of the remaining terms and provisions of this Agreement 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 Agreement.


 


(f) Execution.
This Agreement may be executed in counterparts, all of which when taken together shall be considered one and the same agreement and shall
become effective when counterparts have been signed by each party and delivered to each other party, it being understood that the parties
need not sign the same counterpart. In the event that any signature is delivered by facsimile or electronic transmission or by e-mail
delivery of a “.pdf” format data file, such signature shall create a valid and binding obligation of the party executing
(or on whose behalf such signature is executed) with the same force and effect as if such facsimile or “.pdf” signature page
were an original thereof.


 


(g)
Additional Warrants. The Company may from time to time issue additional warrants (the “Additional Warrants”)
under this Agreement, without requiring the consent of any Holder, with the same terms as the warrants initially issued hereunder.


 


[The
remainder of this page has been left intentionally blank.]


 










     12


     


    

 


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


 


	 	Mechanical Technology, Incorporated	 
	 	 	 	 
	 	By:	 	 
	 	 	Name: Michael Toporek	 
	 	 	Title:  CEO	 


 


[Company
Signature Page to Warrant Agent Agreement]


	 
	 


  










     13


     


    

  


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


 


	 	AMERICAN STOCK TRANSFER & TRUST COMPANY,
    LLC, as Warrant Agent	 
	 	 	 	 
	 	By:	 	 
	 	 	Name:	 
	 	 	Title:	 


 


[Warrant
Agent Signature Page to Warrant Agent Agreement]


 


	 


 


 










     14


     


    




 


Exhibit
A


 


[UNLESS
THIS GLOBAL WARRANT CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY, A NEW YORK CORPORATION
(“DTC”), TO THE COMPANY OR ITS AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY CERTIFICATE ISSUED IS REGISTERED
IN THE NAME OF CEDE & CO. OR SUCH OTHER NAME AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC (AND ANY PAYMENT IS MADE TO CEDE
& CO., OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF
FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL INASMUCH AS THE REGISTERED OWNER HEREOF, CEDE& CO., HAS AN INTEREST HEREIN.


 


TRANSFERS
OF THIS GLOBAL SECURITY SHALL BE LIMITED TO TRANSFERS IN WHOLE, BUT NOT IN PART, TO NOMINEES OF DTC OR TO A SUCCESSOR THEREOF OR SUCH
SUCCESSOR’S NOMINEE AND TRANSFERS OF PORTIONS OF THIS GLOBAL SECURITY SHALL BE LIMITED TO TRANSFERS MADE IN ACCORDANCE WITH THE
RESTRICTIONS SET FORTH IN THE WARRANT AGENT AGREEMENT.


 


ANY
TRANSFER OF THE SECURITIES REPRESENTED BY THIS GLOBAL WARRANT CERTIFICATE IS SUBJECT TO THE CONDITIONS SPECIFIED IN THE WARRANT AGENT
AGREEMENT (THE “WARRANT AGREEMENT”) DATED AS OF [ ], 2021 BETWEEN MECHANICAL TECHNOLOGY, INCORPORATED AND AMERICAN STOCK
TRANSFER & TRUST COMPANY, LLC, SOLELY IN ITS CAPACITY AS WARRANT AGENT. BY ACCEPTING DELIVERY OF THE SECURITIES REPRESENTED BY THIS
GLOBAL WARRANT CERTIFICATE, ANY TRANSFEREE SHALL BE DEEMED TO HAVE AGREED TO BE BOUND BY THE WARRANT AGREEMENT AS IF THE TRANSFEREE HAD
EXECUTED AND DELIVERED THE WARRANT AGREEMENT.]


 


EXERCISABLE
ON OR AFTER [   ], 2021


AND
UNTIL 5:00 P.M. (NEW YORK TIME) ON THE EXPIRATION DATE


 


	CUSIP:	 	 	 
	No.	 	 	Warrants to Purchase [____________]
    Shares


 


Warrant
Certificate


 


WARRANTS
TO PURCHASE COMMON STOCK OF MECHANICAL TECHNOLOGY, INCORPORATED.


 


This
Warrant Certificate certifies that [______________], or registered assigns, is the registered holder of Warrants (the “Warrants”)
to acquire from Mechanical Technology, Incorporated, a Nevada corporation (the “Company”), the aggregate number of
fully paid and non-assessable shares of common stock of the Company, par value $0.001 per share (the “Common Stock”),
specified above for consideration equal to the Exercise Price (as defined in the Warrant Agreement (as defined below)) per share of Common
Stock. The Exercise Price and number of shares of Common Stock and/or type of securities or property issuable upon exercise of the Warrants
are subject to adjustment upon the occurrence of certain events as set forth in the Warrant Agreement. The Warrants evidenced by this
Warrant Certificate shall not be exercisable after and shall terminate and become void as of 5:00 P.M., New York time, on [ ], 2026 (the
“Expiration Date”).


 


The
Warrants evidenced by this Warrant Certificate are part of a duly authorized issue of warrants expiring on the Expiration Date entitling
the Holder hereof to receive shares of Common Stock, and is issued or to be issued pursuant to a Warrant Agent Agreement, dated [ ],
2021 (the “Warrant Agreement”), duly executed and delivered by the Company and American Stock Transfer & Trust
Company, LLC, as warrant agent (the “Warrant Agent,” which term includes any successor warrant agent under the Warrant
Agreement), which Warrant Agreement is hereby incorporated by reference in and made a part of this instrument and is hereby referred
to for a description of the rights, limitation of rights, obligations, duties and immunities thereunder of the Warrant Agent, the Company
and the Holders (“Holders” meaning, from time to time, the registered holders of the warrants issued thereunder).
To the extent any provisions of this Warrant Certificate conflicts with any provision of the Warrant Agreement, the provisions of the
Warrant Agreement shall apply. A copy of the Warrant Agreement may be obtained by the Holder hereof upon written request to the Company
at Mechanical Technology, Incorporated, Attn: Lisa Brennan. Capitalized terms not defined herein have the meanings ascribed thereto in
the Warrant Agreement.





 










     15


     


    

  



 


The
Warrants evidenced by this Warrant Certificate may be exercised, in whole or in part, at any time on or after [ ], 2021 and on or before
the Expiration Date, in the manner and subject to the terms of the Warrant Agreement including, but not limited to, Sections 4 and 9
thereof. Each exercise must be for a whole number of Warrant Shares.


 


The
Warrant Agreement provides that upon the occurrence of certain events the Exercise Price set forth in this Warrant Certificate may, subject
to certain conditions, be adjusted, and that upon the occurrence of certain events the number of shares of Common Stock and/or the type
of securities or other property issuable upon the exercise of the Warrants evidenced by this Warrant Certificate shall be adjusted. The
Warrant Agreement also provides for the automatic conversion of the Warrants under certain circumstances. No fractional share of Common
Stock will be issued upon the exercise of the Warrants evidenced by this Warrant Certificate, but the Company will at its election either
pay the cash value thereof determined as provided in the Warrant Agreement or round the fractional share to the next whole share.


 


Warrant
Certificates, when surrendered at the office of the Warrant Agent by the registered Holder thereof in person or by such Holder’s
legal representative or attorney duly appointed and authorized in writing, may be exchanged, in the manner and subject to the limitations
provided in the Warrant Agreement, but without payment of any service charge, for another Warrant Certificate or Warrant Certificates
of like tenor evidencing in the aggregate the right to purchase a like number of Warrant Shares.


 


Each
taker and holder of this Warrant Certificate, by taking or holding the same, consents and agrees that the holder of this Warrant Certificate
when duly endorsed in blank may be treated by the Company, the Warrant Agent and all other persons dealing with this Warrant Certificate
as the absolute owner hereof for any purpose and as the person entitled to exercise the rights represented hereby or the person entitled
to the transfer hereof on the register of the Company maintained by the Warrant Agent, any notice to the contrary notwithstanding, provided
that until such transfer on such register, the Company and the Warrant Agent may treat the registered Holder hereof as the owner for
all purposes.


 


The
Warrants evidenced by this Warrant Certificate do not entitle any Holder to any of the rights of a stockholder of the Company.


 


This
Warrant Certificate and the Warrant Agreement are subject to amendment as provided in the Warrant Agreement.


 


This
Warrant Certificate shall not be valid or obligatory for any purpose until it shall have been countersigned by the Warrant Agent.


 


[The
remainder of this page has been left intentionally blank.]


	 


 










     16


     


    

 


IN
WITNESS WHEREOF, the undersigned have caused this Global Warrant Certificate to be executed as of the date set forth below.


 


	 	MECHANICAL TECHNOLOGY, INCORPORATED	 
	 	 	 	 
	 	By:	 	 
	 	 	Name:  Michael Toporek	 
	 	 	Title:  CEO	 


 


	Dated: ___________________________________	 
	 	 
	Countersigned:

    AMERICAN
    TRANSFER & TRUST COMPANY, LLC

    as
    Warrant Agent 
	 
	 	 	 
	By:	 	 
	 	Name:	 
	 	Title:	 


 


[Signature
page to Global Warrant Certificate]


	 


 










     17


     


    

 


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 Certificate to purchase ______________ shares of common stock of Mechanical Technology, Incorporated to which the
within Warrant Certificate relates and appoints _______________________________ attorney to transfer said right on the books of Mechanical
Technology, Incorporated with full power of substitution in the premises.


 


	Dated:	 	 


 


	 
	Printed Name of Holder
	 
	Signature of Holder (signature must conform in all
    respects to name of holder as specified on the front page of the Warrant Certificate)
	 
	Title of Signatory (if Holder is not a natural person)
	 
	Address of Transferee:
	 
	 
	 
	 


 


Signature
Guaranteed By:


 


_______________________________________


 


The
signature to this Form of Assignment must correspond with the name as it appears on the face of the Warrant Certificate in every particular.
Officers signing on behalf of a corporation, partnership, trust or other entity must provide evidence of authority to assign the foregoing
Warrant upon request of the Company or Warrant Agent. The signature must be guaranteed by a U.S. chartered bank or by a medallion signature
guarantee from a member of a recognized Signature Medallion Guarantee Program.


 










     18


     


    

  



 


FORM
OF ELECTION TO PURCHASE


 


To
Mechanical Technology, Incorporated:


 


In
accordance with [Warrant Certificate No. enclosed with this Form of Election to Purchase][the Global Warrant Certificate to be delivered
in connection with this Form of Election to Purchase in the manner contemplated by the Warrant Agreement (as defined below)], the undersigned
hereby irrevocably elects to exercise the Warrants evidenced by this Warrant Certificate with respect to Warrant Shares in accordance
with the terms of the Warrant Agent Agreement dated [ ], 2021, between Mechanical Technology, Incorporated, a Nevada corporation, and
American Stock Transfer & Trust Company, LLC, as warrant agent (the “Warrant Agreement”). Terms used and not defined
herein have the meanings specified in the Warrant Agreement.


 


The
Holder hereby agrees to pay the Aggregate Exercise Price, in lawful money of the United States, by certified check payable to the Warrant
Agent, as agent for the Company, or bank draft payable to the order of the Company or by wire transfer of immediately available funds
to an account designated in writing by the Company (or as otherwise agreed to by the Company) delivered to the Warrant Agent, together
with any applicable taxes payable by the undersigned pursuant to the terms of the Warrant Agreement, or, if permitted the cancellation
of such number of Warrant Shares as is necessary, in accordance with the formula set forth in subsection 4(f), to exercise this Warrant
with respect to the maximum number of Warrant Shares purchasable pursuant to the cashless exercise procedure set forth in subsection
4(f).


 


Unless
the Warrant Shares will be delivered electronically via DWAC, the undersigned requests that certificates for the shares of Common Stock
issuable upon this exercise be issued in the name of:


 


	Name:	 	 
	Address:	 	 
	 	 	 


 


Social
Security or Tax I.D. No.: _________________________


 


If
the Warrant Shares will be delivered electronically via DWAC, the undersigned requests that the Warrant Shares issuable upon this exercise
be issued to the following account:


 


	Name of DTC
    Participant:	 
	DTC Participant Number:	 
	Name of Account at DTC
    Participant to be credited with the Warrant Shares:	 
	Account Number at DTC Participant
    to be credited with the Warrant Shares:	 


 


	This Election to Purchase is delivered
    by:
	 
	Signature (and title, if applicable) of Authorized
    Signatory of Holder
	 
	Name of Holder
	 
	Date


 


	 


 










     19


     


    

  



Warrant
Shares Exercise Log


 


	Date	Number
    of Warrant Shares

    Available to be Exercised	Number
    of Warrant

    Shares Exercised	Number
    of Warrant Shares Remaining

    to be Exercised
	 	 	 	 
	 	 	 	 
	 	 	 	 
	 	 	 	 
	 	 	 	 


 


	 


 


 









     20