The WarneA(R) Magazine Extension Kit replaces your SIG P320 mag's existing baseplate to give your handgun a major capacity "boost." Made from anodized aluminum, the Extension Kit features an ergonomic shape that's comfortable in your hands and allows for easier mag swaps. PLEASE NOTE: Magazine not included. Fits SIG P320 9mm magazines Provides +3 rounds of capacity Made from anodized aluminum Ergonomic shape allows for better insertion/removal and comfortable shooting Meets USPSA 141.25mm legal length Designed and made in USA Order today!