Your buffer tube takes a beating every time the rifle cycles, so material matters. This one is 7075 aluminum with a Type 3 Class II hard anodized finish, which is tougher than the Type 2 coating you'll find on cheaper tubes. It's mil-spec diameter, so it accepts standard mil-spec stocks. Six positions let you adjust the length of pull for body armor, heavy coats, or different shooters. Available in four anodized finishes to suit your build.