This unit replaces the magazine floor plate to add approximately 5/8 inch of gripping surface for better comfort and control without sacrificing concealability. It blends with the contours and texture of the handgun and has a factory appearance. The grip extension is made from high impact polymer and withstands drop tests in a range of -20 F to 350 F. This unit fits 9mm, 40S&W, 357SIG, and 45GAP (sub-compact, compact and full size) models only. It will not fit .45 ACP models or XD(M) frames. It does not alter magazine capacity.