This grip extension replaces the magazine base plate.It does not alter the capacity of the magazine, but provides better comfort by adding approximately 5/8 inch of gripping surface.It fits 9mm, 40s&w(sub-compact, compact and full size) models and mod 2 frames.Will not fit.45 acp models, or xdm frames.Caliber: 9mm LugerCapacity: Springfield XD/XD-SModel: Grip ExtensionMaterial: PolymerModel Fit: XD Mod.2Brand Fit: Springfield Armory