17 STATE STREET, 10(TH) FLOOR
[LOGO]                                                             NEW YORK, N.Y. 10004


                           OFFER TO PURCHASE FOR CASH
                     ALL OUTSTANDING SHARES OF COMMON STOCK
           (INCLUDING THE ASSOCIATED RIGHTS TO PURCHASE COMMON STOCK)
                                       OF
                                   OEA, INC.
                                       BY
                             OEA MERGER CORPORATION
                     AN INDIRECT WHOLLY OWNED SUBSIDIARY OF
                                 AUTOLIV, INC.

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    THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT 12:00 MIDNIGHT, NEW YORK CITY
TIME, ON MONDAY, APRIL 24, 2000, UNLESS THE OFFER IS EXTENDED.
- --------------------------------------------------------------------------------

                                                                  March 24, 2000

To Brokers, Dealers, Commercial Banks, Trust Companies and Other Nominees:

    We have been appointed by OEA Merger Corporation, a Delaware corporation
("Purchaser") and an indirect wholly owned subsidiary of Autoliv, Inc., a
Delaware corporation ("Parent") to act as Information Agent in connection with
Purchaser's offer to purchase all of the outstanding shares of common stock, par
value $0.10 per share, including the associated rights to purchase common stock
(collectively, the "Shares"), of OEA, Inc., a Delaware corporation (the
"Company"), at a price of $10.00 per Share, net to the seller in cash, upon the
terms and subject to the conditions set forth in the Offer to Purchase dated
March 24, 2000 (the "Offer to Purchase") and the related Letter of Transmittal
(which, together with any amendments or supplements thereto, collectively
constitute the "Offer"), copies of which are enclosed herewith. The Offer is
being made in connection with the Amended and Restated Agreement and Plan of
Merger, dated as of February 12, 2000 (the "Merger Agreement"), among Parent,
Purchaser and the Company. The Merger Agreement provides, among other things,
that Purchaser will be merged with and into the Company (the "Merger") following
the satisfaction or waiver of each of the conditions to the Merger set forth in
the Merger Agreement.

    Please furnish copies of the enclosed materials to those of your clients for
whose accounts you hold Shares registered in your name or in the name of your
nominee.

    For your information and for forwarding to your clients, we are enclosing
the following documents:

    (1) The Offer to Purchase.

    (2) The Letter of Transmittal to be used by stockholders of the Company in
       accepting the Offer, including a Certification of Taxpayer Identification
       Number on Substitute Form W-9. Facsimile copies of the Letter of
       Transmittal (with manual signatures) may be used to tender Shares.

    (3) A letter to stockholders of the Company from Dr. Charles B. Kafadar,
       President and Chief Executive Officer of the Company, together with a
       Solicitation/Recommendation Statement on Schedule 14D-9, dated March 24,
       2000 filed by the Company with the Securities and Exchange Commission,
       which includes the recommendation of the Board of Directors of the
       Company that stockholders accept the Offer and tender their Shares to
       Purchaser pursuant to the Offer.

    (4) A printed form of letter which may be sent to your clients for whose
       account you hold Shares in your name or in the name of your nominee with
       space provided for obtaining such clients' instructions with regard to
       the Offer.

    (5) The Notice of Guaranteed Delivery to be used to accept the Offer if
       certificates representing Shares are not immediately available or if time
       will not permit all required documents to reach the Depositary (as
       defined below) prior to the Expiration Date (as defined in Section 1 of
       the Offer to Purchase) or if the procedures for book-entry transfer
       cannot be completed on a timely basis.

    (6) Guidelines of the Internal Revenue Service for Certification of Taxpayer
       Identification Number on Substitute Form W-9. Stockholders who fail to
       complete and sign the Substitute Form W-9 may be subject to a required
       federal backup withholding tax of 31% of the gross proceeds payable to
       such stockholder or other payee pursuant to the Offer. See Section 2 of
       the Offer to Purchase.

    (7) A return envelope addressed to First Chicago Trust Company of New York
       (the "Depositary") for your use only.

    Your attention is directed to the following:

    1. The tender price is $10.00 per Share, net to the seller in cash, without
interest, upon the terms and conditions set forth in the Offer to Purchase.

    2. The Board of Directors of the Company unanimously (i) determined that the
Offer, the Merger and the Merger Agreement are advisable, fair to, and in the
best interests of, the Company's stockholders, (ii) approved the Merger, the
Offer, the Merger Agreement and the other transactions contemplated by the
Merger Agreement and (iii) recommends that the Company's stockholders accept the
Offer and tender their Shares pursuant thereto, and approve and adopt the Merger
Agreement.

    3. The Offer and withdrawal rights will expire at 12:00 midnight, New York
City time, on Monday, April 24, 2000, unless the Offer is extended.

    4. The Offer is being made for all of the outstanding Shares. The Offer is
conditioned upon, among other things (i) there being validly tendered and not
properly withdrawn prior to the expiration date of the Offer that number of
Shares which represents more than fifty percent of the total issued and
outstanding Shares on a fully diluted basis (excluding Shares held by the
Company or any of its subsidiaries) and (ii) the expiration or termination of
any and all waiting periods applicable to the transactions contemplated by the
Merger Agreement under the Hart-Scott-Rodino Antitrust Improvements Act of 1976,
as amended. The Offer is also subject to other terms and conditions. See
Section 15 of the Offer to Purchase.

    5. Stockholders who tender Shares will not be obligated to pay brokerage
fees or commissions to the Information Agent or the Depositary or, except as set
forth in Instruction 6 of the Letter of Transmittal, stock transfer taxes on the
purchase of Shares by Purchaser pursuant to the Offer.

    Upon the terms and subject to the conditions of the Offer (including, if the
Offer is extended or amended, the terms and conditions of any such extension or
amendment), Purchaser will accept for payment and pay for all Shares which are
validly tendered on or prior to the Expiration Date and not theretofore properly
withdrawn pursuant to the Offer. In all cases, payment for Shares accepted for
payment pursuant to the Offer will be made only after timely receipt by the
Depositary of (i) certificates representing such Shares (or a timely
confirmation of a book-entry transfer of such Shares into the Depositary's
account at The Depository Trust Company, pursuant to the procedures described in
Section 2 of the Offer to Purchase), (ii) a properly completed and duly executed
Letter of Transmittal (or a manually signed facsimile thereof) with any required
signature guarantees (or, in connection with a book-entry transfer, an Agent's
Message (as defined in Section 2 of the Offer to Purchase)), and (iii) all other
documents required by the Letter of Transmittal.

    If holders of Shares wish to tender, but it is impracticable for them to
forward their certificates or other required documents prior to the expiration
of the Offer, a tender may be effected by following the guaranteed delivery
procedures specified under Section 2 of the Offer to Purchase.

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    Purchaser will not pay any fees or commissions to any broker or dealer or to
any other person (other than the Depositary and the Information Agent) in
connection with the solicitation of tenders of Shares pursuant to the Offer.
Purchaser will, however, upon request, reimburse you for customary mailing and
handling expenses incurred by you in forwarding the enclosed materials to your
clients. Purchaser will pay or cause to be paid any stock transfer taxes payable
on the transfer of Shares to it, except as otherwise provided in Instruction 6
of the Letter of Transmittal.

    YOUR PROMPT ACTION IS REQUESTED. WE URGE YOU TO CONTACT YOUR CLIENTS AS
PROMPTLY AS POSSIBLE. PLEASE NOTE THAT THE OFFER AND WITHDRAWAL RIGHTS WILL
EXPIRE AT 12:00 MIDNIGHT, NEW YORK CITY TIME, ON MONDAY, APRIL 24, 2000, UNLESS
THE OFFER IS EXTENDED.

    Any inquiries you may have with respect to the Offer should be directed to,
and additional copies of the enclosed materials may be obtained by contacting,
the undersigned at (800) 223-2064 (call toll free).

                               Very truly yours,

                   Georgeson Shareholder Communications Inc.

    NOTHING CONTAINED HEREIN OR IN THE ENCLOSED DOCUMENTS SHALL CONSTITUTE YOU
OR ANY PERSON AS AN AGENT OF PURCHASER, PARENT, THE COMPANY, THE DEPOSITARY OR
THE INFORMATION AGENT, OR ANY AFFILIATE OF ANY OF THE FOREGOING, OR AUTHORIZE
YOU OR ANY OTHER PERSON TO GIVE ANY INFORMATION OR USE ANY DOCUMENT OR MAKE ANY
STATEMENTS ON BEHALF OF ANY OF THEM IN CONNECTION WITH THE OFFER OTHER THAN THE
DOCUMENTS ENCLOSED HEREWITH AND THE STATEMENTS CONTAINED THEREIN.

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