The Davidson Defense USA AR15 Heavy Duty Pistol Buffer Tube Kit is engineered for optimum performance and durability. Constructed from premium 6061 T6 aluminum with a MIL-SPEC Type III Class 2 hardcoat anodized finish, this kit ensures longevity and reliability in any environment. MIL-SPEC Type III Class 2 hardcoat anodized Made from durable 6061 T6 aluminum Compatible with carbine buffer and action springs Designed for AR-15/M16/M4 lower receivers Outside diameter: 1.2" Includes receiver end plate and castle nut Choose this complete kit for unmatched quality and performance in your firearm setup.