Aim Sports Vertical Round Foregrip, Short – Black. This foregrip is only 3" in length and weighs only 3 oz. Affixes to standard picatinny and NAR Stanag 4694 rails. No mounting hardware needed. Simply unscrew the center stem and slip the gip onto the rail, then screw the center stem back in and line up the nub on the end of the stem with a notch in the rail and tighten. Made from black polymer.