The SuperSASS? (Semi-Automatic Sniper System) was originally designed for use by the US Military but a civilian model is available to discerning shooters who demand superb accuracy. The SuperSASS? Gen II has a fully adjustable stock and an adjustable gas system built to accommodate suppressed and un-suppressed fire. The SuperSASS? Gen II is the ultimate tactical rifle system on the market.Specifications: Caliber: 7.62 x 51 Barrel: HB Black Nitride 416R Stainless Steel Barrel Length: 20" Twist Rate: 1:10 RH Muzzle Device: Armalite Tactical Brake Front Sight Base: Mil- Spec 1913 Handguard: 15" Armalite Gen II MLok Free Float Stock Magpul: PRS Gen II Upper Receiver: Armalite AR-10A Lower Receiver: Armalite AR-10A Trigger Trigger: Tech Length: 43" Weight: 11.4LBS