Upgrade your AR15 rifle and experience a whole new level of performance with the Wilson Combat AR-15 Bolt Upgrade Kit! Increased extraction, ejection power, and gas ring durability will transform your shooting experience. These parts are not only up to military standards, they exceed them - enhancing your gun beyond its current performance. Get ready for upgraded recoil control, enhanced accuracy, and a whole new level of precision shooting. Package Includes:MK3 ejector springExtra-power chrome silicon extractor springStainless steel utilized gas ring with four turns