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 annual report of Global Brass and Copper Holdings, Inc. (the “Company”) on Form 10-K for the period ending December 31, 2015, as filed with the Securities and Exchange Commission (the “Report”), and pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, 18 U.S.C. Section 1350, each of the undersigned hereby certifies that to the best of their 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.
 
Date: March 9, 2016
 
/s/ John J. Wasz
John J. Wasz
Chief Executive Officer

/s/ Robert T. Micchelli
Robert T. Micchelli
Chief Financial Officer

This written statement accompanies the Report pursuant to Section 906 of the Sarbanes-Oxley Act of 2002 and shall not, except to the extent required by the Sarbanes-Oxley Act of 2002, be deemed filed by the Company for purposes of Section 18 of the Securities Exchange Act of 1934.

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