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                                                                     Exhibit 4.3

                         NOTICE OF GUARANTEED DELIVERY


     This Notice of Guaranteed Delivery, or a form substantially equivalent to
this form, must be used to accept the Offer (as defined below) if certificates
for the shares of common stock of AROC Inc. are not immediately available, or if
time will not permit all other documents required by the Letter of Transmittal
to be delivered to the Depositary prior to the Expiration Date (as defined in
the Offer to Purchase (defined below)).  Such form may be delivered by hand or
transmitted by mail or overnight courier, or (for Eligible Institutions (as
defined below) only) by facsimile transmission, to the Depositary.  THE ELIGIBLE
INSTITUTION THAT COMPLETES THIS FORM MUST COMMUNICATE THE GUARANTEE TO THE
DEPOSITARY AND MUST DELIVER THE LETTER OF TRANSMITTAL AND CERTIFICATES FOR
SHARES TO THE DEPOSITARY WITHIN THE TIME SHOWN HEREIN.  FAILURE TO DO SO COULD
RESULT IN A FINANCIAL LOSS TO SUCH ELIGIBLE INSTITUTION.

                        The Depositary for the Offer is:

                          REGISTRAR & TRANSFER COMPANY

                               Delivery Address:

               By Hand Delivery,                By Facsimile:
          Overnight Courier or Mail:
                                               (908) 497-2311
       Registrar and Transfer Company
      Attn: Reorganization Department
              10 Commerce Drive
             Cranford, NJ  07016
               (800) 368-5948

     DELIVERY OF THIS INSTRUMENT TO AN ADDRESS OTHER THAN AS SET FORTH ABOVE OR
TRANSMISSION OF INSTRUCTIONS VIA A FACSIMILE NUMBER OTHER THAN THE ONE LISTED
ABOVE WILL NOT CONSTITUTE A VALID DELIVERY.

     THIS FORM IS NOT TO BE USED TO GUARANTEE SIGNATURES.  IF A SIGNATURE ON A
LETTER OF TRANSMITTAL IS REQUIRED TO BE GUARANTEED BY AN ELIGIBLE INSTITUTION
UNDER THE INSTRUCTIONS THERETO, SUCH SIGNATURE GUARANTEE MUST APPEAR IN THE
APPLICABLE SPACE PROVIDED IN THE SIGNATURE BOX ON THE LETTER OF TRANSMITTAL.

LADIES AND GENTLEMEN:

     The undersigned hereby tenders to AROC Inc., a Delaware corporation (the
"Company"), upon the terms and subject to the conditions set forth in the Offer
to Purchase, dated May 14, 2001 (the "Offer to Purchase"), and the related
Letter of Transmittal (which, as amended from time to time, together constitute
the "Offer"), receipt of which is hereby acknowledged, the number of shares of
common stock, par value $0.001 per share (the "Shares"), of the Company listed
below, pursuant to the guaranteed delivery procedure set forth in the Offer to
Purchase.
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            Number of Shares:_________________________

            Name(s):__________________________________
                        (Please Print)

            Certificate Nos. (if available):__________


            __________________________________________


            __________________________________________

            Address:__________________________________


            __________________________________________

            __________________________________________


               GUARANTEE (NOT TO BE USED FOR SIGNATURE GUARANTEE)

     The undersigned, a firm or other entity that is a member in good standing
of the Security Transfer Agent's Medallion Program, the New York Stock Exchange
Medallion Program or the Stock Exchange Medallion Program (an "Eligible
Institution"), hereby guarantees (i) that the above-named person(s) has a net
long position in the Shares being tendered within the meaning of Rule 14e-4
promulgated under the Securities Exchange Act of 1934, as amended, (ii) that
such tender of Shares complies with Rule 14e-4, and (iii) to deliver to the
Depositary at one of its addresses set forth above certificate(s) for the Shares
tendered hereby, in proper form for transfer, together with a properly completed
and duly executed Letter(s) of Transmittal (or manually signed facsimile(s)
thereof), with any required signature guarantee(s) and any other required
documents, all within three trading days after the date hereof.


_______________________________          _______________________________
Name of Firm                             Authorized Signature

_______________________________          _______________________________
Address                                  Name

_______________________________          _______________________________
City, State, Zip Code                    Title

_______________________________
Area Code and Telephone Number:

Dated:___________________, 2001

     DO NOT SEND SHARE CERTIFICATES WITH THIS FORM. YOUR SHARE  CERTIFICATES
MUST BE SENT WITH THE LETTER OF TRANSMITTAL.


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