The Brownells AR-15 Rifle Length Buffer Tube is machined from high quality 7075 aluminum and boasts a matte black hardcoat anodized finish. Fits standard AR-15 and M16 lower receivers and rifle length buttstocks. Machined from 7075 aluminum Matte black hardcoat anodized 9 5/8” length 1.110” diameter The Brownells AR-15 Rifle Length Buffer allows you to use the highest quality components in your AR-15 build.