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                                                                   EXHIBIT 10.18

                                  AMENDMENT TO
                       THE AMENDED AND RESTATED LABOR POOL
                                    AGREEMENT

      This Amendment to the AMENDED AND RESTATED LABOR POOL AGREEMENT ("Labor
Pool Agreement"), by and between KLEINKNECHT ELECTRIC COMPANY, INC. (NY)
("KEC-NY"), of 940 Eighth Avenue, New York, NY 10014, and IPC INFORMATION
SYSTEMS, INC., now IPC INFORMATION SYSTEMS, LLC ("IPC") of 88 Pine Street, New
York, NY 10005, is entered into this 15th day of June, 2004.

      WHEREAS, KEC-NY and IPC are signatories to the Labor Pool Agreement under
which KEC-NY and IPC continue to employ workers represented by Local 3 and Local
3 (White Plains) (the "Unions") on a pooled basis under the terms of KEC-NY's
current collective bargaining agreement(s) with the Unions; and

      WHEREAS, some of the said workers perform services for IPC in connection
with the ITS Division of IPC, certain assets of which are to be sold (the "Sold
Operations"); and

      WHEREAS, the purchaser of those assets, and any successor or assign
thereof ("I.T.S. Holdings, LLC"), desires to enter into a temporary
subcontracting arrangement with IPC for the provision, by IPC, of workers to
service the Sold Operations; and

      WHEREAS, KEC-NY and the Unions have agreed to the above-described
arrangements; and

      WHEREAS, the parties desire to memorialize these modifications to the
Labor Pool Agreement;

      NOW THEREFORE, the parties agree as follows:

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      1. IPC may continue to employ workers on a pooled basis under the terms of
the Labor Pool Agreement for any purpose within the contemplation of such
agreement and, additionally, in order to provide the services of pooled
employees to I.T.S. Holdings, LLC in connection with the Sold Operations (the
"Subcontracting Arrangement"). The Subcontracting Arrangement shall be upon such
terms as IPC and I.T.S. Holdings, LLC may mutually agree that are consistent
with the Labor Pool Agreement, provided, however, the duration of the
Subcontracting Arrangement shall be for a period of twelve months, commencing
with the first day of the month next following the closing of the purchase of
the assets of the Sold Operations ("Subcontracting Period"). IPC may terminate
the Subcontracting Arrangement prior to the end of the Subcontracting Period on
90 days written notice. In such event, IPC shall continue to remit the monthly
fees to KEC-NY pursuant to paragraph 4(b) of the Labor Pool Agreement in respect
of the Sold Operations for the balance of the Subcontracting Period, following
which the provisions of paragraph 3 hereof shall apply. KEC-NY represents that
upon the termination of the Subcontracting Arrangement, it intends to use the
pooled employees from the Subcontracting Arrangement for its own operations.

      2. KEC-NY represents and warrants that the Unions have consented to the
arrangement described in paragraph 1 hereof. This representation is included
under KEC-NY's indemnification obligations set forth in paragraph 9 of the Labor
Pool Agreement.

      3. Effective upon termination of the Subcontracting Period, the monthly
fees payable to KEC-NY by IPC pursuant to paragraph 4(b) of the Labor Pool
Agreement shall be reduced by sixty percent (60%).

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      4. Effective upon termination of the Subcontracting Period, the standby
letter of credit described in Paragraph 5 of the Labor Pool Agreement shall be
reduced to the aggregate amount of $1 million.

      5. Paragraph 10 of the Labor Pool Agreement is hereby deleted in its
entirety and shall be without further force and effect.

      6. IPC waives any right to terminate under Paragraph 14 of the Labor Pool
Agreement with respect to the May 2004 Collective Bargaining Agreement.

      7. The effective date of this Amendment shall be the closing date of the
sale of the Sold Operations, or, July 1, 2004, whichever occurs first.

      8. Except as herein provided, the terms of the Labor Pool Agreement shall
remain unmodified.

IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be signed
by their duly authorized officers the day and year first above written.

                                  KLEINKNECHT ELECTRIC COMPANY, INC. (NY)

                                  By: /s/ Richard P. Kleinknecht
                                      ------------------------------------------
                                      Richard P. Kleinknecht, President

                                  IPC INFORMATION SYSTEMS, LLC

                                  By: /s/ Anthony Scimeca
                                      ------------------------------------------
                                      Anthony Scimeca, Vice President

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