Modern technology meets "tried and true": K-SPEC buffers utilize an innovative captured compression system to absorb recoil and minimize muzzle rise - without any complex or expensive parts to wear down and fail. Paired with KAK Industry's flatwire spring, you have a simple drop-in replacement that eliminates bolt bounce, flattens muzzle rise, and smooths out recoil. KAK Industry developed our K-SPEC buffer system to offer the best value in recoil mitigation, 100% made in America for a lifetime of dependable use. This kit includes a 3.8oz H1 OR 4.7oz H2 OR 5.5oz H3 Carbine-length K-SPEC buffer, flatwire spring, and buffer install tool. Please note: This Mfg: Kak Industry Llc.