Presolicitation DEPT OF DEFENSE DEPT OF THE NAVY is seeking to procure 17 GAU-21 A-kits for the CH-53K aircraft. These kits, necessary to incorporate the CH-53K GAU-21 Window and Door Common Defensive Weapon System (WDCDWS) Sikorsky capabilities, will be sourced from Sikorsky Aircraft Corporation, a Lockheed Martin Company. Sikorsky is the designer and developer of the CH-53K helicopter and is the only known responsible source with the required knowledge, capability, experience, technical data, and test equipment. This procurement is authorized under Title 10USC 2304(c)(1) and FAR 6.302-1(a)(2) for other than full and open competition. The Government will consider capability statements received within fifteen days of the publication of this notice. For subcontracting opportunities, contact Jason Lockwood at 203-225-3657 or jason.t.lockwood@lmco.com.