This Sig Sauer P320 Carry Medium Grip Module is a genuine factory replacement part finished in a standard black polymer. It is designed to house P320 or P250 Fire Control Units in 9mm, .40 S & W, or .357 SIG that do not require a manual safety cutout. The "Carry" size combines a full-length grip for increased capacity with a shorter rail section for use with 3.9-inch compact or carry-length slides. This "Medium" circumference assembly comes ready for immediate installation and includes a pre-installed, reversible magazine catch.