Foregrip mounts onto 1913 MIL-STD Picatinny rail of a handguard. Storage compartment with tight-sealing door for batteries and cleaning supplies. Designed to be grasped by the support hand for better support and pointability. Brand: NcStar Includes: Picatinny Foregrip Materials: High Quality Polymer Compatibility: AR-15, Rifles with a Picatinny Rail Weight: 2 oz Length: Rail Mount: 1.7 in, Handle: 5.4 in Color: Black Warranty: Lifetime