(SOT required for purchase. Silencers may not be combined with other product when shipping.) Caliber: 45 AUTO - Sound: 133 dB (Dry) - Material: Grade 9 Titanium and Stainless Steel - Size: 7.9 x 1.38 - Weight: 12 oz - Threads: .578-28 tpi / M16x1 - The SRD45 .45AUTO Pistol Silencer features a Grade 9 Titanium tube and 17-4PH baffles allowing for light weight and durability. The SRD45 features a booster for use with Browning Titling Barrel type pistols. A fixed barrel spacer is also available. The SRD45 ships with both .578-24tpi and M16x1mm LH pistons. The SRD45 can be converted to use with 9mm or .40AUTO host pistols by using the appropriate threaded accessory piston.