AAC Illusion 9 Piston M13.5x1 LH

This Advanced Armament Piston enhances the versatility of an AAC Silencer by allowing the suppressor to be swapped between various different host firearms with different barrel threads. All that's necessary to convert the silencer to be compatible with a different barrel thread pitch is to select the proper piston and replace the existing one residing in the rear of the sound suppressor. All AAC pistons are constructed of heat treated stainless steel with a bead blasted matte finish, and each is engraved to indicate the thread diameter, thread pitch and direction of rotation for installation. Common Use: 1/2"-28 Thread: Most Common Aftermarket 9mm Barrels M13.5x1 LH Thread: Factory Sig Sauer, HK and S&W M&P 9mm Barrels 9/16"-24 Thread: Most Common Aftermarket 40 S&W Barrels 9/16-28 Thread: Alternative Aftermarket 40 S&W Barrel Thread Pattern M14.5x1 LH Thread: Factory Sig Sauer and HK 40 S&W Barrels