The AR-STONER Pistol Buffer Tube is perfect for upgrading an existing or building a new AR-15 pistol. This buffer tube is machined to strict military standards to provide an excellent fit and reliable function. The AR-STONER buffer tube is machined from 6061-T6 aluminum and given a hard coat anodized finish to withstand years of abuse. Includes(1) Mil-Spec Pistol Buffer Tube w/ Foam Insert(1) 3 oz. Buffer(1) Carbine length buffer spring(1) Regular End Plate(1) Castle Nut