Sig Sauer P320 Cal-X P320-M18 9mm Carry Coyote (3)10rd Mags X-Change Kit CALX-M18-CSS-MS-10

The SIG Sauer Caliber X‑Change Kit — P320 → M18 Carry (CALX‑M18‑CSS‑MS‑10) is a factory OEM conversion kit that turns a compatible P320 fire‑control unit into the commercial M18 carry configuration. Finished in coyote PVD, the kit ships as a drop‑in package with a 3.9″ optics‑ready M18 slide (SIG‑LOC/MHS footprint), 3.9″ barrel and recoil assembly, a carry‑length coyote grip module with manual safety, and three 10‑round magazines for 10+1 capacity. The slide accepts ROMEO‑M17/MHS‑pattern optics and includes SIGLITE sighting provisions with a removable rear night‑sight plate — delivering military‑style ergonomics and optics capability without the need for gunsmithing. Confirm your P320 FCU (manual‑safety vs non‑safety, caliber) before installing the kit. Sig Sauer P320 Cal-X P320-M18 9mm Carry Coyote (3)10rd Mags X-Change Kit CALX-M18-CSS-MS-10