From the beginning, the P320 was built to be a pistol that could adapt to meet the user's specific needs. From grip modules and magazines to custom slides, barrels, and optics, the P320 can be configured in thousands of different ways to make your P320 unique and exactly the pistol you are looking for. This drop in Fire Control Unit allows you to build a P320 pistol exaclty how you want using SIG's Grip Modules, Slides and Barrels. Firearm Features Exclusive Titanium Nitride Frame Titanium Nitride Skeletonized Trigger Compatible with all 9mm / 357SIG / 40SW P320 Post-Upgrade accessories