The LWRCI Ultra Compact Stock Kit Black Synthetic for AR-15, M16 from LWRC delivers a proven UCIW-inspired solution that shortens the firearms overall length by a full inch while preserving handling quality and reliability. This stock system includes the stock, receiver extension, index plate, buffer, recoil spring and castle nut, all designed to work together for seamless installation and dependable performance when mounted on an AR-15 or AR rifle platform. Lightweight and rugged, it features integral sling attachment points, easy one-hand adjustments and an excellent cheekweld, with a rubber buttpad to prevent slippage during firing. The receiver extension provides four positions to finely tune the length of pull, enhancing fit and comfort across different shooting stances and gear configurations. Derived from LWRCIs UCIW project, this stock kit is a versatile option for shortening the overall length of your rifle without compromising control or durability. Built with a black synthetic composition and finished to withstand hard use, it combines practical function with streamlined form for operators and enthusiasts seeking a compact, reliable stock system.