The KynSHOT RB5001 Recoil Buffer is a hydraulic buffer system designed and optimized to fit any AR-15 using a Mil-Spec style rifle length A1 or A2 fixed stock buffer tube (internal depth 9.5"). The RB5001 can be paired with any style rifle buffer spring, and is a simple drop-in replacement for all buffer systems on the market. The RB5001 reduces felt recoil by 30%, improving the shooters overall accuracy and eliminating muzzle flip.