EXHIBIT 4.16.3

February 17, 1999

Ed Pollock, Esq.
Able Telcom Holding Corp.
1601 Forum Place, Suite 1110
West Palm Beach, FL 33401

Dear Ed:

This letter is to confirm our conversations regarding our investment in Able
Telcom Holding Corp. (the "Company") .The Company acknowledges and agrees that
the Registration Statement has not been declared effective as required by the
Registration Rights Agreement; that a Triggering Event therefore occurred on
October 28, 1998; and that under the Registration Rights Agreement Palladin
Securities L.L.C., Halifax Fund, L.P., Palladin Partners I, L.P., The Gleneagles
Fund Company, Palladin Overseas Fund Limited and Colonial Penn Life Insurance
Company (collectively, the "Pa1ladin Investors") have the right to redeem their
Preferred Shares in accordance with the terms of the Articles of Amendment, and
that such right of redemption shall remain in effect until the shares of
Preferred Stock are converted or redeemed in accordance with the terms of the
Articles of Amendment. The Company further acknowledges that the circumstances
described in Section 3 (d) (viii) (x) of the Articles of Amendment and Section
2(b) (i) of the Registration Rights Agreement are applicable because the Company
failed to obtain effectiveness of the Registration Statement on or prior to
October 28, 1998. Capitalized terms used herein but not defined herein shall
have the meanings assigned thereto in the Registration Rights Agreement, the
Articles of Amendment or the Convertible Preferred Stock Purchase Agreement.

         The Company has determined that it is in its best interest for the
parties to agree that:

1.       The Company shall use its best efforts to cause the registration of the
         Shares pursuant to the terms of the Registration Rights Agreement
         within 90 days of the date hereof (the "Registration Period");

2.       The undersigned hereby waives, to the extent provided herein, all
         outstanding defaults under the terms of the Series B Preferred Stock
         and the Registration Rights Agreement and hereby withdraws its previous
         Notice of Redemption at Option of Holder Upon Triggering Event
         delivered to Able on or about January 19, 1999;

3.       The undersigned hereby agrees that it will not during the Registration
         Period attempt to exercise any default remedy it may have under the
         Registration Rights Agreement; and

4.       The Company agrees if necessary, to permit and to facilitate the
         understanding set forth in Section 2.11 of the Securities Purchase
         Agreement between Cotton Communications, Inc. and the Palladin
         Investors, dated even date herewith, including, without limitation, by
         amending the Company's Articles of Amendment.

         By signifying its agreement to the foregoing, the parties agree that
the Palladin Investors do not waive any other rights they may have under the
Articles of Amendment, the Registration Rights Agreement, the Preferred Stock
Purchase Agreement or any other agreement between the Company and the Palladin
Investors. Specifically, if Effective Registration has not occurred during the
Registration Period, the waiver in Section 2 above

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shall no longer be in effect and the Pal1adin Investors shall have all rights
and remedies they would have had as if this Agreement had never been entered
into by the parties.

         Please indicate your agreement to the foregoing by signing in the space
provided.

                               Sincerely,

                               HALIFAX FUND, L.P.
                               THE GLENEAGLES FUND COMPANY
                               PALLADIN OVERSEAS FUND LIMITED
                               COLONIAL PENN LIFE INSURANCE

                               By:      _________________________
                                        By:      The Palladin Group, L. P. as
                                        Attorney-in-Fact and Investment Advisor
                                        By:
                                        Title:

                               PALLADIN SECURITIES L.L.C.

                               By:      ________________________
                                        Name:
                                        Title:

                               PALLADIN PARTNERS I, L.P.

                               By:      ________________________
                                        By:  Palladin Asset Management L.L.C. as
                                        Attorney-in-Fact
                                        By:
                                        Title:

Accepted and Agreed to:

ABLE TELCOM HOLDING CORP.

By:      _______________________
         Name:
         Title: