E. I. DU PONT DE NEMOURS AND COMPANY

OFFER TO EXCHANGE SHARES OF
CLASS B COMMON STOCK OF CONOCO INC. FOR
EACH SHARE OF COMMON STOCK OF E. I. DU PONT DE NEMOURS AND COMPANY
UP TO AN AGGREGATE OF SHARES OF

COMMON STOCK OF E. I. DU PONT DE NEMOURS AND COMPANY HELD BY

UNITED STATES PERSONS

To Our Clients:

Enclosed for your consideration is an Offering Circular - Prospectus dated
, 1999 (the "Offering Circular - Prospectus") and a form of Letter of
Transmittal WHICH ARE FURNISHED TO YOU FOR INFORMATION ONLY AND MAY NOT BE USED
BY YOU TO TENDER SHARES OF DUPONT COMMON STOCK (the "Letter of Transmittal"; and
together with the Offering Circular - Prospectus, the "Exchange Offer") relating
to the offer by E. I. du Pont de Nemours and Company ("DuPont") to exchange
shares of Class B common stock, par value $.01 per share, of Conoco Inc.
("Conoco Common Stock") for each share tendered of common stock, par value $.30
per share, of DuPont ("DuPont Common Stock") held by a United States person up
to an aggregate of
shares of DuPont Common Stock tendered and exchanged.

The Exchange Offer is available only to DuPont stockholders who are United
States persons, as explained on page 25 of the Offering Circular-Prospectus. A
United States person for purposes of the Exchange Offer is any person that is:

- an individual who is a United States citizen or United States resident
for United States federal income tax purposes;

- a corporation, partnership, limited liability company or other entity
created or organized in the United States or under the laws of the United
States or of any state within the United States;

- an estate which is subject to United States income tax on all of its
income, regardless of the source of such income; or

- a trust if a United States court is able to exercise primary supervision
over the administration of the trust, and one or more United States
persons have the authority to control all substantial decisions of the
trust. Such a trust includes, without limitation, any United States
pension trust organized under Section 401(a) of the Internal Revenue
Code.

DUPONT STOCKHOLDERS ARE URGED TO CONSULT THEIR TAX ADVISORS REGARDING THEIR
STATUS AS UNITED STATES PERSONS IN ORDER TO DETERMINE THEIR ELIGIBILITY TO
PARTICIPATE IN THE EXCHANGE OFFER. DUPONT STOCKHOLDERS WHO ARE NOT UNITED STATES
PERSONS ARE INELIGIBLE TO PARTICIPATE IN THE EXCHANGE OFFER AND SHOULD NOT
COMPLETE THIS TENDER INSTRUCTION FORM. If you are not a United States person,
you should contact D.F. King or your broker for more information regarding a
substantially concurrent cash offer being made to non-United States persons by
DuPont. United States persons are not eligible to participate in the cash offer.

The material is being forwarded to you as the beneficial owner of shares of
DuPont Common Stock carried by us in your account but not registered in your
name. A tender of such shares of DuPont Common Stock may only be made by us as
the registered holder and pursuant to your instructions. Therefore, DuPont urges
holders of shares of DuPont Common Stock registered in the name of a broker,
dealer, commercial bank, trust company or other nominee to contact such
registered holder promptly if they wish to accept the Exchange Offer.

Accordingly, we request instructions as to whether you wish us to tender
any or all such shares of DuPont Common Stock held by us for your account
pursuant to the terms and conditions set forth in the enclosed Offering
Circular - Prospectus and the related Letter of Transmittal.

Your instructions to us should be forwarded as promptly as possible in
order to permit us to tender shares of DuPont Common Stock in accordance with
the provisions of the Exchange Offer. The Exchange Offer will expire at 12:00
Midnight, New York City time, on , , 1999, or if extended by
DuPont, the

latest date and time to which extended (the "Expiration Date"). Shares of DuPont
Common Stock tendered pursuant to the Exchange Offer may be withdrawn, subject
to the procedures described in the Offering Circular - Prospectus, at any time
prior to the Expiration Date and after , 1999, if not theretofore
accepted for exchange by DuPont.

Your attention is directed to the following:

1. The Exchange Offer is for up to an aggregate of shares of DuPont
Common Stock.

2. DuPont's obligation to accept shares of DuPont Common Stock tendered in
the Exchange Offer is subject to certain conditions specified in the
Offering Circular - Prospectus.

3. No domestic stock transfer taxes will be payable as a result of the
transaction. DuPont will pay all foreign stock transfer taxes, except as
otherwise provided in Instruction 6 of the Letter of Transmittal.

If you wish to have us tender any or all of your shares of DuPont Common
Stock, please so instruct us by completing, executing and returning to us the
instruction form which appears on the reverse side of this letter. The
instruction form is to be completed only by United States persons. Persons who
are not United States persons can not participate in the Exchange Offer.

INSTRUCTIONS

I acknowledge receipt of your letter and the enclosed material referred to
therein relating to the Exchange Offer of E. I. du Pont de Nemours and Company
("DuPont") of DuPont common stock, par value $.30 per share ("DuPont Common
Stock") held by a United States person.

This will instruct you to tender the shares of DuPont Common Stock
indicated below (or, if no number is indicated below, all shares) held by you
for my account, pursuant to the terms of and conditions set forth in the
Offering Circular - Prospectus and the Letter of Transmittal.

Box 1 [ ] Please tender all of my shares of DuPont Common Stock held by you
for my account.

Box 2 [ ] Please tender (number) of the shares of DuPont
Common Stock held by you for my account.

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ODD-LOTS

[ ] By checking this box, I represent that I owned beneficially and of record as
of , 1999, an aggregate of less than 100 shares of DuPont
Common Stock and am tendering all such shares.

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SIGNATURE

BY SIGNING BELOW, I HEREBY CERTIFY THAT I AM A UNITED STATES PERSON AS DEFINED
ON PAGE 2 ABOVE AND ON PAGE 25 OF THE OFFERING CIRCULAR -- PROSPECTUS AND THAT I
AM ELIGIBLE TO PARTICIPATE IN THIS EXCHANGE OFFER.

Dated: -----------------------------------------------------------
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SIGNATURE(S)
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PLEASE PRINT NAME(S) HERE

UNLESS A SPECIFIC CONTRARY INSTRUCTION IS GIVEN IN THE SPACE PROVIDED, YOUR
SIGNATURE(S) HEREON SHALL CONSTITUTE AN INSTRUCTION TO US TO TENDER ALL OF YOUR
SHARES OF DUPONT COMMON STOCK.

PLEASE RETURN THIS FORM TO THE BROKERAGE FIRM MAINTAINING YOUR ACCOUNT, NOT
THE EXCHANGE AGENT, INFORMATION AGENT OR DUPONT.