The Advanced Technology AR-15 civilian buffer tube assembly package fits most AR-15 and AR variants. It features a 6-position, 7.8" hard-coat anodized 6061-T6 aluminum buffer tube with a slanted back and commercial thread and tube diameters of 1.17". This assembly also comes with an AR-15 recoil plug, buffer spring, and a steel castle nut and locking ring. Features: Commercial diameter tube for optimal fit into commercial buttstock Constructed of military type III anodized, 6061 T6 aluminum Includes steel castle nut and locking ring Includes AR-15 recoil plug and buffer spring Virtually indestructible Limited lifetime warranty Made in USA