If you're looking to slow down your BCG to ensure proper cycling then choose from one of LBE's three Heavy Recoil Buffers (H1, H2, or H3). The correct buffer weight depends on the type and length of the barrel, gas port size, gas system length, as well as the type and caliber of the ammo used. This H3 Carbine Buffer comes with 3 Tungsten weights. For use with a Carbine Buffer Tube only. LBE Unlimited is a leading producer of US Made gun parts and accessories.