The KynSHOT RB5006 Hydraulic Recoil Buffer is designed to fit AR10/.308 rifles with a fixed stock. Made using 17-4 stainless steel, the KynSHOT RB5006 Recoil Buffer is a proven system that has seen heavy use with civilian competition shooters, law enforcement personnel and the United States Armed Forces. This buffer has patented damping technology to absorb the shock of impact from the bolt carrier's rearward motion and prevent bolt bounce as a new cartridge is chambered. The KynSHOT RB5006 reduces felt recoil by 20-30%, while largely eliminating muzzle flip. The improvement in weapon accuracy- specifically second and third shot accuracy- is large as shooters report that their time to reacquire a target decreases, and in many cases never leaves their scope sights. DO NOT USE IN 9mm AR-15s Features Drop-in replacement Reduce felt recoil Improve reliability