UTG Stock Assembly is a black fixed A2 buttstock assembly for AR-15 platforms, molded from impact-resistant advanced polymer with an aluminum extension tube. Compatible with non-adjustable rifle extension tubes. Complete kit includes A2 extension tube, recoil spring, standard carbine buffer assembly (3.0 oz), stock spacer, and screw. Features a storage pocket for cleaning kit, small parts, and other accessories. Total weight 25.0 oz. Safety note Follow all manufacturer installation instructions. Verify proper function and secure mounting before use. Comply with local firearm laws and regulations.