Hei (HEIIQ) 10-Q 2007 Q3 Quarterly report

EXHIBIT 32.1

CERTIFICATION PURSUANT TO

18 U.S.C. SECTION 1350,

AS ADOPTED PURSUANT TO

SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

In connection with the Quarterly Report of HEI, Inc. (the “Company”) on Form 10-Q for the quarter ended June 2, 2007, as filed with the Securities and Exchange Commission on the date hereof (the “Report”), I, Mark B. Thomas, Chief Executive Officer and Chief Financial Officer of the Company, certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley AcT of 2002, that to the best of my knowledge:

     (1) The Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and

     (2) The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

/s/ Mark B. Thomas  

Mark B. Thomas 

Chief Executive Officer and Chief Financial Officer 

Date: July 16, 2007

A signed original of this written statement required by Section 906 has been provided to HEI, Inc. and will be retained by HEI, Inc. and furnished to the Securities and Exchange Commission or its staff upon request.

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