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                                                                     EXHIBIT 4.3

                              TEPPCO PARTNERS, L.P.
   CERTIFICATE EVIDENCING LP UNITS REPRESENTING LIMITED PARTNERSHIP INTERESTS


                                                         3,916,547 Class B Units


This certifies that DUKE ENERGY TRANSPORT AND TRADING COMPANY, a Colorado
corporation, is the registered holder of THREE MILLION NINE HUNDRED SIXTEEN
THOUSAND FIVE HUNDRED FORTY-SEVEN and No/100 (3,916,547) CLASS B UNITS

representing Class B Units of Limited Partnership Interests in TEPPCO PARTNERS,
L.P., a limited partnership formed under the laws of the State of Delaware (the
"Partnership"), transferrable on the books of the Partnership, in person or by
duly authorized attorney, upon surrender of this Certificate properly endorsed
and accompanied by a property executed Application for Transfer of the Class B
Units represented by this Certificate. This Certificate and the Class B Units
represented hereby are issued and shall in all respects be subject to all of the
provisions of the Second Amended and Restated Agreement of Limited Partnership
of the Partnership, as amended or restated from time to time, to all of which
the holder, by acceptance hereof, assents and to the additional terms and
provisions on the reverse side hereof.

         Witness the signature of the duly authorized officer of the General
Partner of the Partnership.

                             TEXAS EASTERN PRODUCTS PIPELINE COMPANY, as General
                             Partner


                             By:         /s/ William L. Thacker
                             Name:         William L. Thacker
                             Title: President and Chief Executive Officer

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         TEPPCO Partners, L.P., a limited partnership formed under the laws of
the State of Delaware (the "Partnership"), will furnish to the holder and each
assignee of the Certificate and the Class B Units evidenced hereby, without
charge, on written request to the Partnership at its principal place of
business, P. O. Box 2521, Houston, Texas 77252-2521, a copy of the Agreement of
Limited Partnership of the Partnership, as amended or restated from time to
time.

         The holder, by accepting this Certificate, is deemed to have (i)
requested admission as, and agreed to become, a Limited Partner or a Substituted
Limited Partner (as defined in the Partnership Agreement, the terms of which are
incorporated herein by reference), as applicable, and to have agreed to comply
with and be bound by and to have executed the Partnership Agreement, (ii)
represented and warranted that the holder has all right, power and authority
necessary to enter into the Partnership Agreement, (iii) appointed the General
Partner and, if a liquidator shall be appointed, the liquidator of the
Partnership as the holder's attorney to execute, swear to, acknowledge and file
any document, including, without limitation, the Partnership Agreement, any
amendment to the Partnership Agreement and the Certificate of Limited
Partnership of the Partnership, necessary or appropriate for the holder's
admission as a Limited Partner or a Substituted Limited Partner, as applicable,
in the Partnership and as a party to the Partnership Agreement, (iv) given the
powers of attorney provided for in the Partnership Agreement and (v) made the
waivers and given the approvals contained in the Partnership Agreement.

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                              TEPPCO PARTNERS, L.P.

         NO TRANSFER OF THE LP UNITS EVIDENCED HEREBY WILL BE REGISTERED ON THE
BOOKS OF TEPPCO PARTNERS, L.P. (THE "PARTNERSHIP"), UNLESS THE LP UNIT
CERTIFICATES EVIDENCING THE LP UNITS TO BE TRANSFERRED ARE SURRENDERED FOR
REGISTRATION OF TRANSFER AND AN APPLICATION FOR TRANSFER OF LP UNITS HAS BEEN
EXECUTED BY A TRANSFEREE EITHER (A) ON THE FORM SET FORTH BELOW OR (B) ON A
SEPARATE APPLICATION THAT THE PARTNERSHIP WILL FURNISH ON REQUEST WITHOUT
CHARGE. A TRANSFEROR OF THE LP UNITS SHALL HAVE NO DUTY TO THE TRANSFEREE WITH
RESPECT TO EXECUTION OF THE TRANSFER APPLICATION IN ORDER FOR SUCH TRANSFEREE TO
OBTAIN REGISTRATION OF THE TRANSFER OF THE LP UNITS.

                      APPLICATION FOR TRANSFER OF LP UNITS

         The undersigned ("Assignee") hereby applies for transfer to the name of
the Assignee of the LP Units evidenced hereby.

         The Assignee (a) requests admission as a Substituted Limited Partner
and agrees to comply with and be bound by, and hereby executes, the Agreement of
Limited Partnership of TEPPCO Partners, L.P. (the "Partnership"), as amended or
restated to the date hereof (the "Partnership Agreement"), (b) represents and
warrants that the Assignee has all right, power and authority and, if an
individual, the capacity necessary to enter into the Partnership Agreement, (c)
appoints the General Partner and the liquidator if one is appointed his attorney
to execute, swear to, acknowledge and file any document, including, without
limitation, the Partnership Agreement, any amendment to the Partnership
Agreement and the Certificate of Limited Partnership of the Partnership,
necessary or appropriate for the Assignee's admission as a Substituted Limited
Partner and as a party to the Partnership Agreement, (d) gives the powers of
attorney provided for in the Partnership Agreement and (e) makes the consents
and waivers and gives the approvals contained in the Partnership Agreement.
Capitalized terms not defined herein have the meanings assigned to such terms in
the Partnership Agreement.


Date:
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                                                Signature of Assignee

Social Security or other identifying
        number of Assignee
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                                            Name and Address of Assignee


------------------------------------ 
         Purchase Price
  (including commissions, if any)

Type of Entity (check one): [ ] Individual [ ] Partnership [ ] Corporation 
[ ] Trust [ ] Other (specify):

         
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Note: If the Assignee is a broker, dealer, bank, trust company, clearing
corporation, other nominee holder or an agent of any of the foregoing, and is
holding for the account of any other person, this application should be
completed by an officer thereof or, in the case of a broker or dealer, by a
registered representative who is a member of a registered national securities
exchange or a member of the National Association of Securities Dealers, Inc.,
or, in the case of any other nominee holder, a person performing a similar
function. If the Assignee is a broker, dealer, bank, trust company, clearing
corporation, other nominee owner or an agent of any of the foregoing, the above
certification as to any Person for whom the Assignee will hold the LP Units
shall be made to the best of the Assignee's knowledge.

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         You have acquired an interest in TEPPCO Partners, L.P., Houston, Texas
77252, whose taxpayer identification number is 76-0291058. The Internal Revenue
Service has issued TEPPCO Partners, L.P. the following as tax shelter
registration number: 90036000017

         You must report this REGISTRATION NUMBER TO THE INTERNAL REVENUE
SERVICE IF YOU CLAIM ANY DEDUCTION, LOSS, CREDIT, OR OTHER TAX BENEFIT OR REPORT
ANY INCOME BY REASON OF YOUR INVESTMENT IN TEPPCO PARTNERS, L.P.

         You must report the registration number (as well as the name and
taxpayer identification number of TEPPCO Partners, L.P.) on Internal Revenue
Service Form 8271. FORM 8271 MUST BE ATTACHED TO THE RETURN ON WHICH YOU CLAIM
THE DEDUCTION, LOSS, CREDIT, OR OTHER TAX BENEFIT OR REPORT ANY INCOME.

         ISSUANCE OF A REGISTRATION NUMBER DOES NOT INDICATE THAT THIS
INVESTMENT OR THE CLAIMED TAX BENEFITS HAVE BEEN REVIEWED, EXAMINED, OR APPROVED
BY THE INTERNAL REVENUE SERVICE.
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