Caliber: .45 ACP Sound Reduction: 30 dB Length: 6.5'' Diameter: 1.375'' Materials: 7075 Aluminum Mount: .578-28 Includes: (1) .45 ACP Suppressor Direct Thread Piston (1) .578-28 The Python is constructed of 7075 aluminum and mounts with an interchangeable piston core. It is capable of being fired on 4.45cal, .40cal, 10mm, or 9mm weapons by simply swapping out the rear piston for the appropriate mount. It ships with .578x28 threads and has the following direct thread pistons also available (M16x1RH, M16x1LH, M14.5x1LH, 9/16x24, & 1/2x28). Sound reduction: 30dB