Sig Sauer P320 X-Series Grip Module, 9/40/357 Compact, Medium. Install your P320/P250 firing control unit into this compact grip module assembly to convert your P320 or P250 carry chambered in 9mm, .357 SIG, .40 S&W to a small size X-series grip. Made from durable polymer with a black grip, this module requires the 9mm, .357 SIG and .40 AUTO slide and barrel. This X-Series grip features an extended beavertail and high undercut trigger guard to promote a higher grip along with improved recoil control. Ergonomic Design Black Extended Beavertail Higher Undercut Trigger Guard Product Specifications Manufacturer: Sig Sauer Model: P320 X-Series Caliber: 9mm, .40 S&W, .357 SIG Capacity: N/A Features: Black, Compact, Small, Polymer