Pearce Grip's Grip Extension replaces the magazine base plate, but retains all other factory components. It does not alter the capacity of the magazine and provides better comfort and control by adding approximately 1/2 inch of gripping surface. It blends with the contours and texture of the handgun and has a factory appearance. The grip extension is made from high impact polymer. A filler piece is provided for Glock models with a semi-circular cut-out in the lower front area of the grip body. This filler piece allows for installation on all Mid and Full Size Glocks, Models 17,18,19,22,23,24,25,31,32,34,35,37,38 - Full Metal Lined Magazines Only.These grip extensions replace the magazine base plate providing better comfort and control by adding approximately 1/2 inches of gripping surface. They do not alter the capacity of the magazine. Fits Gen 3 models 17, 18, 19, 22, 23, 24, 25, 31, 32, 34, 35, 37, 38 - full metal lined magazines only. 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 provide comfort by increasing the length of the grip 1/2 inches over stock dimensions They provide an easier means of manually extracting the magazines Provides magazine identification via Mag-Track for those that rotate magazine usage