AR-15 Pistol Grip with Storage Compartment. Mounts onto AR-15/ M4/ M16 lower receivers, and uses standard Pistol Grip bolt/screw from LPK. Ergonomic design to fit comfortably in the Operators hand. Finger Grooves, Thumb Rest, Grip Texture, and w/ Back-Strap Tang. Storage Compartment can store two each CR123A batteries, spare parts, or emergency survival supplies.