The only thing better than a normal pistol barrel is a threaded pistol barrel. All pistol silencers require one. SilencerCo noticed a market need for high quality pistol barrels and they stepped in to offer them. Holding to the same commitment to quality as all SilencerCo's products, the threaded barrels are tough enough to hold up under the harshest conditions. The barrels are constructed from 416R stainless steel and finished with a tough Black Nitride Finish.Specifications and Features: Barrel Length: 5 Inches Cartridge: 9mm Luger Compatible With: Glock 17 Finish: Black Salt Bath Nitride Material: Stainless Steel Threaded Muzzle: Yes Threads: 1/2"-28 Twist: 1:10"