ARC style helmet rail._x000D_ High density polymer construction._x000D_ 4 position accessory rail connectors provide non-snag attachment points for quick attach or release a variety of accessories including: Flashlights, Camera, Visor, COMs headset, Strobe, Mandible, Battery Pack...etc._x000D_ Corner buckle receiver for gas and O2 mask strap kit attachments._x000D_ Come with screw and nut for installing onto the helmet. (drilling is necessary if your helmet do not have fitting hole)_x000D_ Fits all ACH, MICH, PASGT and lightweight marine helmets. _x000D_ NOTE: Helmet is not included in this item. _x000D_