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                                                                      EXHIBIT 16


                       [KPMG PEAT MARWICK LLP LETTERHEAD]


December 17, 1996

Securities and Exchange Commission
Washington, D.C. 20549

Ladies and Gentlemen:

We were previously principal accountants for Zycon Corporation (the Company)
and, under the date of January 19, 1996, we reported on the consolidated
financial statements of Zycon Corporation and subsidiary as of and for the
years ended December 31, 1995 and 1994, and for each of the years in the
three-year period ended December 31, 1995. On December 6, 1996, our appointment
as principal accountants was terminated. We have read the Company's statements
included under Item 4 of its Form 8-K dated December 6, 1996, and we agree with
such statements, except that we are not in a position to agree or disagree with
the Company's statements that (i) on December 4, 1996, the Company entered into
a definitive Agreement and Plan of Merger with Hadco Corporation and Hadco
Acquisition Corporation, pursuant to which Hadco Acquisition Corporation has
agreed to acquire the Company; (ii) our dismissal was made at Hadco Acquisition
Corporation's request; (iii) on December 12, 1996, the Company's Audit
Committee of the Board of Directors ratified our dismissal; (iv) on December
12, 1996, Arthur Andersen LLP was engaged by the Company as the principal
accountant to audit the Company's consolidated financial statements; and (v)
during the Company's two most recent fiscal years and the subsequent interim
period prior to engaging Arthur Andersen LLP, neither the Company, nor anyone
on its behalf, consulted Arthur Andersen LLP regarding (1) either the
application of accounting principles to a specified transaction, either
completed or proposed; or the type of audit opinion that might be rendered on
the Company's consolidated financial statements, and either a written report
was provided to the Company or oral advice was provided that Arthur Andersen
LLP concluded was an important factor considered by the Company in reaching a
decision as to the accounting, auditing or financial reporting issue; or (2)
any matter that was the subject of a disagreement on any matter of accounting
principles or practices, financial statement disclosure, or auditing scope or
procedures, or a reportable event as defined in Item 304(a)(2) of Regulation
S-K.

Very truly yours,

KPMG Peat Marwick LLP


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