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                                                                    EXHIBIT 10.4

September 28, 2004

VIA E-MAIL
----------

Proposed Offering Participant
Named in Accompanying E-Mail Cover

              Re:      Proposed Offering of Unsecured Promissory Notes, Common
                       Stock and Warrants
                       ---------------------------------------------------------

Dear Proposed Offering Participant:

         We are writing in regard to a proposed offering ("OFFERING") of
unsecured promissory notes due March 31, 2006 ("NOTES"), common stock ("COMMON
Stock"), and five-year common stock purchase warrants ("WARRANTS", and together
with the Notes and Common Stock, the "SECURITIES") of Telenetics Corporation
("TELENETICS" or the "COMPANY"). As you are aware, Telenetics is seeking funds
to repay an existing promissory note in the principal amount of $700,000 held by
Dolphin Direct Equity Partners, L.P. and to support Telenetics' working capital
requirements.

         Telenetics proposes to issue up to $1,000,000 of Securities to a
limited number of accredited investors in a private placement transaction that
would close on or about September 30, 2004, provided that certain conditions are
met. These conditions would include, among others, that Telenetics raise at
least $840,000 in gross proceeds from the sale of the Securities. Subject to
final approval by Telenetics, participants in the Offering may elect to pay for
the Securities either with cash in U.S. dollars or by surrendering all or a
portion of existing indebtedness owed to the participant by Telenetics.

         The Notes and Warrants would be in substantially the forms attached as
exhibits to this letter. For each one U.S. dollar invested in a Note by a
participant in the Offering, the participant would receive 1.5 shares of Common
Stock and Warrants to purchase an additional 1.25 shares of common stock
("WARRANT SHARES"). No fractional shares of Common Stock would be issued in the
Offering, and no Warrants would be issued for the purchase of a fractional
number of Warrant Shares. Instead, the amount invested would be reduced to the
extent necessary to avoid the issuance of fractional shares, and the excess
purchase price will be refunded to the participant (in the case where cash is
used to fund the purchase price) or remain as outstanding indebtedness.

         Because the Offering would be conducted as a private placement
transaction, the Securities would be "restricted securities" within the meaning
of Rule 144 promulgated under the Securities Act of 1933 ("SECURITIES ACT") and
you would be unable to resell any of the Securities without either registration
under the Securities Act or the existence of another exemption from such
registration requirement. The Common Stock and the Warrant Shares would carry
piggyback registration rights as described in an exhibit to this letter.





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Proposed Offering Participant
September 28, 2004
Page 2

         By this letter, Telenetics offers you the opportunity to participate in
the Offering. By signing below, you indicate your commitment to participate in
the Offering. You also represent to Telenetics that you are, and at the time of
consummation of your participation in the Offering will be, an "accredited
investor" as defined in Rule 501 of Regulation D under the Securities Act, you
have such experience in business and financial matters that you are capable of
evaluating the merits and risks of an investment in the Securities, and that you
acknowledge that an investment in the Securities is speculative and involves a
high degree of risk. You further represent that you have had the opportunity to
ask questions of and receive answers from, or obtain additional information
from, the executive officers of Telenetics concerning the financial and other
affairs of Telenetics, and to the extent deemed necessary in light of your
personal knowledge of Telenetics' affairs, you have has asked such questions and
received answers to your full satisfaction. In addition, you represent that you
would be acquiring the Securities solely for your own account for the purpose of
investment and not with a view to or for sale in connection with a distribution,
and that you do not have a present intention to resell any of the Securities,
nor a present arrangement (whether or not legally binding) or intention to
effect any distribution of any of the Securities to or through any person or
entity, and that you will not have any such intention or arrangement at the time
of consummation of your participation in the Offering.

         Reports and documents filed by Telenetics with the Securities and
Exchange Commission are available free-of-charge by the contacting the
undersigned at Telenetics or by accessing the Securities and Exchange Commission
web site at http://www.sec.gov. Telenetics encourages you to review those
reports and documents, particularly the "Risk Factors" described therein, and to
consult with your professional advisors to the extent you deem appropriate when
making your decision.

                          [continued on following page]





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Proposed Offering Participant
September 28, 2004
Page 3

         Assuming the foregoing is acceptable to you, please sign and fill in
the information requested below and return it to the undersigned on or before
September 30, 2004. Following receipt, we will notify you as to how to submit
your payment for the Securities. Thank you for your consideration.

                                         Sincerely,

                                         TELENETICS CORPORATION

                                         /s/ David L. Stone

                                         David L. Stone, President and CEO

Attachments





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Proposed Offering Participant
September 28, 2004
Page 4

Exact name in which the Securities would be issued:_____________________________

Dollar amount of Note desired to be purchased: $________________________________

Form of payment (e.g., cash, cancellation of specific type of indebtedness):
________________________________________________________________________________

____________________________________________________
Signature

____________________________________________________
Print Name

____________________________________________________
Title of signer (if signing on behalf of an entity)

____________________________________________________
Name of entity (if signing on behalf of an entity)





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                                    EXHIBIT A
                                    ---------

                                  Form of Notes

[See Exhibit 10.5 to this Form 8-K]



<PAGE>

                                    EXHIBIT B
                                    ---------

                                Form of Warrants

[See Exhibit 10.6 to this Form 8-K]



<PAGE>

                                    EXHIBIT C
                                    ---------

                               Registration Rights

1. PIGGY-BACK REGISTRATION. If at any time when there is not an effective
federal registration statement covering all of the Securities, 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, the Company shall
send to each holder ("HOLDER") of Securities that are not then registered
(collectively, "REGISTRABLE SECURITIES") written notice of such determination
and, if within ten (10) days after receipt of such notice, any such Holder shall
so request in writing, (which request shall specify the Registrable Securities
intended to be disposed of by the Holders), the Company will cause the
registration under the Securities Act of all Registrable Securities which the
Company has been so requested to register by the Holder, to the extent requisite
to permit the disposition of the Registrable Securities so to be registered,
provided that if at any time after giving written notice of its intention to
register any securities and prior to the effective date of the registration
statement filed in connection with such registration, the Company shall
determine for any reason not to register or to delay registration of such
securities, the Company may, at its election, give written notice of such
determination to such Holder and, thereupon, (i) in the case of a determination
not to register, shall be relieved of its obligation to register any Registrable
Securities in connection with such registration and (ii) in the case of a
determination to delay registering, shall be permitted to delay registering any
Registrable Securities being registered for the same period as the delay in
registering such other securities. The Company shall include in such
registration statement all or any part of such Registrable Securities such
Holder requests to be registered; provided, however, that the Company shall not
be required to register any Registrable Securities that are eligible for sale
pursuant to Rule 144(k) of the Securities Act; and provided further, that the
Holder has promptly furnished in writing to the Company or the Company's counsel
such information as the Company or the Company's counsel shall reasonably
require in connection with the registration statement.

         In the case of an underwritten public offering, if the managing
underwriter(s) or underwriter(s) should reasonably object to the inclusion of
the Registrable Securities in such registration statement, then if the Company
after consultation with the managing underwriter should reasonably determine
that the inclusion of such Registrable Securities, would adversely affect the
offering contemplated in such registration statement, and based on such
determination recommends inclusion in such registration statement of fewer or
none of the Registrable Securities of the Holders, then (x) the number of
Registrable Securities of the Holders included in such registration statement
shall be reduced pro rata among such Holders (based upon the number of
Registrable Securities requested to be included in the registration), if the
Company after consultation with the underwriter(s) recommends the inclusion of
fewer Registrable Securities, or (y) none of the Registrable Securities of the
Holders shall be included in such registration statement, if the Company after
consultation with the underwriter(s) recommends the inclusion of none of such
Registrable Securities; provided, however, that if securities are being offered
for the account of other persons or entities as well as the Company, such
reduction shall not represent a greater fraction of the number of Registrable
Securities intended to be offered by the Holders than the fraction of similar
reductions imposed on such other persons or entities (other than the Company).

                                      C-1





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2.       INDEMNIFICATION.

         (a) INDEMNIFICATION BY THE COMPANY. The Company shall, notwithstanding
any termination of the Purchase Agreement, indemnify and hold harmless each
Holder, the officers, directors, agents, brokers (including brokers who offer
and sell Registrable Securities as principal as a result of a pledge or any
failure to perform under a margin call of the Company's common stock),
investment advisors 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, costs of preparation and attorneys' fees) and
expenses (collectively, "LOSSES") (as determined by a court of competent
jurisdiction in a final judgment not subject to appeal or review), as incurred,
arising solely out of or based solely upon any untrue or alleged untrue
statement of a material fact contained in the registration statement, any
prospectus or any form of prospectus or in any amendment or supplement thereto
or in any preliminary prospectus, or arising solely out of or based solely upon
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 the light of the
circumstances under which they were made) not misleading, except to the extent,
but only to the extent, that such untrue statements or omissions are based
solely upon information regarding such Holder or such other Indemnified Party
(as defined below) furnished in writing to the Company by such Holder expressly
for use therein, which information was reasonably relied on by the Company 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. 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 these registration
rights provisions.

         (b) INDEMNIFICATION BY PURCHASERS. The Holders shall, severally and not
jointly, indemnify and hold harmless the Company, the 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 law, from and against all Losses (as
determined by a court of competent jurisdiction in a final judgment not subject
to appeal or review), as incurred, arising solely out of or based solely upon
any untrue statement or alleged untrue statement of a material fact contained in

                                      C-2





<PAGE>

the registration statement, any prospectus, or any form of prospectus or form of
prospectus or in any amendment or supplement thereto or in any preliminary
prospectus, 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 (in the case of any prospectus or supplement thereto, in the light of
the circumstances under which they were made) not misleading, to the extent, but
only to the extent, that such untrue statement or omission or alleged untrue
statement or omission is contained in any information so furnished in writing by
such Holder or other Indemnified Party to the Company specifically for inclusion
in the registration statement or such prospectus and that such information was
reasonably relied upon by the Company for use in the registration statement,
such prospectus or such form of prospectus 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.

         (c) CONDUCT OF INDEMNIFICATION PROCEEDINGS. If any action, claim, suit,
investigation or proceeding (including without limitation, an investigation or
partial proceeding, such as a deposition), whether commenced or threatened
("PROCEEDING") is brought or asserted against any person entitled to indemnity
hereunder (an "INDEMNIFIED PARTY"), such Indemnified Party promptly shall 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
the Purchase 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; or (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 (which shall be reasonably
acceptable to the Indemnifying Party) that a conflict of interest is likely to
exist if the same counsel were to represent such Indemnified Party and the
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 or delayed. 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.

                                      C-3





<PAGE>

                  All 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 these registration rights provisions) shall be paid to the
Indemnified Party, as incurred, within ten (10) business 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 hereunder is
unavailable to an Indemnified Party because of a failure or refusal of a
governmental authority to enforce such indemnification in accordance with its
terms (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 these registration
rights provisions, 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 these registration rights provisions 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 subsection (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. No person guilty of fraudulent misrepresentation (within the meaning
of Section 11(f) of the Securities Act) shall be entitled to contribution from
any person who was not guilty of such fraudulent misrepresentation.

                  The indemnity and contribution agreements contained in these
registration rights provisions are in addition to any liability that the
Indemnifying Parties may have to the Indemnified Parties.

                                      C-4