These units replace the magazine base plate and retain all other factory components. They do not alter the capacity of the magazine. These units will add 5/8 inches additional length for better control and comfort. Features: These units blend with the contours and texture of the handgun giving a factory appearance They are made from high impact polymer and withstand drop tests at temperatures from -20 to 350 deg F They form the next logical finger positioning feature to provide control and comfort without sacrificing conceal ability Provides magazine identification via Mag-Track for those that rotate magazine usage