The Advanced Technology A5102240 is a versatile buffer tube assembly kit, compatible with majority of AR-15 and AR variants. It includes a six-position AR-15 buffer tube, manufactured from resilient hard-coat anodized 6061-T6 aluminum. This tube comes with mil-spec thread and tube diameters of 1.19\" and 1.15\" respectively.In addition to the buffer tube, the assembly package is equipped with an AR-15 recoil plug and buffer spring. It also features a steel castle nut and locking ring, both of which are military-grade and coated for additional durability and longevity.