This unit replaces the magazine base plate on the Springfield XDS/XDE/XDS MOD2 in 45ACP, 40 S&W and 9mm single stack magazines. This extension adds one round capacity to the magazine and increases the grip length by approximately 7/8"" inch. Caliber 9mm Luger, 40 S&W, 45 ACPModel Magazine ExtensionFinish BlackMaterial PolymerCapacity 1Brand Fit SpringfieldModel Fit Springfield XDS, XDE,XDS Mod 2