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                                                                    EXHIBIT 4.13

                       AMENDED AND RESTATED ATTACHMENT A

The Services to be provided by Cardinal Securities, L.L.C. ("CS") and the
compensation to be received by CS from Eltrax Systems, Inc. (the "Company")
shall be as follows:

         CS has introduced the Company to institutional investors for a Private
         Placement of up to USD$7,000,000.00 on a Best Efforts Basis. In
         consideration of its services, CS shall be entitled to receive a fee
         equal to 6% of the aggregate cash proceeds to the Company (the "Fee")
         from the Private Placement. The Fee shall be payable promptly
         following the initial closing of the Private Placement and on each
         subsequent or additional closing (each a "Closing Date"), 1% of the
         Fee will be paid in the form of cash and 5% of the Fee ("Stock Fee")
         will be paid by the issuance by the Company of a number of shares of
         its common stock (the "Common Stock") having a value equal to such
         amount with the Common Stock being valued at $4.00 per share for such
         purposes in respect of the initial closing and $4.50 per share for
         such purposes in respect of each subsequent closing. In consideration
         of the USD$4,000,000.00 initial investment by Cavallo Capital into
         Eltrax Systems, Inc., CS is entitled to receive USD$40,000 and 50,000
         shares of Common Stock; provided, however, that if the Closing Price
         of the Common Stock on the date of the effectiveness of the
         registration Statement (as hereinafter defined) is less than $4.00 per
         share, then CS shall be entitled to an additional number of shares of
         Common Stock equal to (a) the amount determined by dividing
         $200,000.00 by the Closing Price on such date minus (b) 50,000; and
         provided further, however, that if the Closing Price of the Common
         Stock on the date upon which the shares of Common stock comprising the
         Stock Fee in respect of each subsequent closing are issued is less
         than $4.50 per share, then CS shall be entitled to an additional
         number of shares of Common Stock equal to (a) the amount determined by
         dividing the value of the Stock Fee payable in the respect of each
         subsequent closing by the Closing Price on such date minus (b) the
         number of shares of Common Stock comprising the Stock Fee in respect
         of each such subsequent closing, where such number of such shares is
         determined based upon the Common Stock being valued at $4.50 per
         share. This schedule form applies to subsequent funding by Cavallo
         Capital up to USD$7,000,000. The Company will include the shares of
         Common Stock issuable to CS pursuant to this agreement in the
         registration statement to be filed to register for resale the
         securities sold in the Private Placement (the "Registration
         Statement"). In addition, the Company will reimburse CS its reasonable
         out-of-pocket travel and other expenses incurred in connection with
         the Private Placement in an amount not in excess of USD$5,000.00.

AGREED TO AND ACCEPTED THIS 28th day of AUGUST, 2000.

CARDINAL SECURITIES, L.L.C.              ELTRAX SYSTEMS, INC.


/s/ Scott F. Koch                        /s/ William P. O'Reilly
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By: Scott F. Koch                        By: William P. O'Reilly
Its: Senior Managing Director            Its: Chief Executive Officer