Commercial-spec stock molded from impact resistant advanced polymer using advanced molding technology. 6 adjusting positions from 10.75" to 7". Tight tolerance controlled threads and dimensions for a secure fit. Complete with recoil spring, aluminum buffer, tear drop receiver plate and locking ring. Includes a Commercial receiver extension tube precision machined from 6061/T6 aluminum alloy with Type III Class II hard coat for best wear resistance. Made in the USA. 922R Compliant. One year limited warranty. Weight: 18.2 oz.