Our HERA H15G grip is made of fiberglass-reinforced polymer to improve impact resistance. The H15G pistol grip provides an internal storage place to store items such as batteries. In relation to its weight, it is one of the most stable pistol grips on the market. The grip is designed to be used with AR-15, M4 systems that feature a standard mil-spec receiver. The H15G grip can also be used on systems using a grip interface compatible with the AR-15, M4 systems.