NOTE: These kits ship in a cardboard box with a foam cutout from SIG. We felt our customers deserved better, so we ship these kits in a Sig Hard Case at no additional charge. 

The P320 XFIVE TXG Caliber X-Change Kit is the ultimate upgrade kit for the serious shooter. Increase the weight of your pistol thanks to the innovative TXG tungsten-infused grip module. This is the first of its kind in the firearms industry with the weight of steel and the flex of polymer, reducing muzzle flip by up to 50%.  The recoil system uses a solid steel guide rod and a 14lb 1911-style spring, with an additional 12lb spring and (2) 17rd Magazines included. All of these new features coupled with the removable magwell & grip weight, ROMEO1PRO optic-ready slide, 5” bull barrel, and Dawson Precision® fiber optic adjustable sights catapults this cal-x kit ahead of the competition and sets a new standard.


  • XFIVE Complete Slide
  • 5″ Bull Barrel
  • 14lb & 12lb Recoil Spring & Solid Steel Guide Rod
  • TXG Grip Module
  • (2) 17 Round Magazines
  • Sig Hard Case

*Note, only for use on 9mm/ .357SIG / .40S&W firing control units (FCU). It will not function with a .45 ACP FCU.