This Sig Sauer P320 Compact Small Grip Module is a factory replacement frame specifically engineered for Fire Control Units chambered in .45 ACP. Finished in a standard black polymer, this module features a "Small" circumference that provides a slimmer profile for better control and an easier reach to the trigger. It is designed to fit compact slide lengths and includes a pre-installed, reversible magazine catch for quick setup. Please note that due to dimensional differences in the magwell and internal dimensions, this module is not compatible with 9mm, .40 S & W, or .357 SIG components.