BATTLEGRIP Model BG-16 fits all M4 / M16 / AR-15 series rifles and clones, Armalite AR-10 and Knights Armament Corp SR-25 / MK -11 Mod O. Any rifle configured to take a standard M16 / AR-15 grip will accept BATTLEGRIP. Grip includes foam anti-rattle battery spacers, stainless steel Dry-Lok fastener, installation tool and complete instructions for easy installation. Batteries and spare parts not included. Internal Battery Storage Compartment Aggressive Texture Improved Ergonomics Weather Resistant Cover