Guaranteed to give you an edge, ODIN Works has designed their PMBs (Pistol Magazine Bases) with the competitive and noncompetitive shooter in mind. Introducing the Smith & Wesson M&P PMB: Ergonomically machined to fit perfectly in the palm of your hand for effortless stripping, the weighted base allows for rapid mag changes and 4 to 5 extra rounds all while remaining well within the 140 mm gauge limits of USPSA.