Snag free design. No sharp edges prevent tangling of the rifle with the shooter's sling, molle gear, or other kit; Modular VBOST (Vehicle Borne Operations Sling Tab); Two different types of ambidextrous sling mounting options, including QD swivel sockets; Integrated color matched rubber butt pad for secure shoulder placement, along with increased durability; Simple modular design; Includes: BCM 7075T6 Mil-Spec Receiver Extension, Locking Nut M4 (Castle), Mil-Spec Carbine Action Spring, Carbine Buffer, BCM QD Swivel Mount End Plate; Black Color; All parts are Made in the USA