The M18 was recently issued to all branches of the U.S. Military and was chosen as the official sidearm of the U.S. Marine Corps. The P320-M18 is the commercial version that brings the same unprecedented accuracy, extreme reliability and unmatched durability the military demands. The P320-M18 comes standard with SIGLITE night sights and a removable night sight rear plate. The slide is optic ready and directly compatible with the ROMEO1 PRO. The slide and grip module are the same coyote tan as the military version, and it includes (1) 17 round magazine and (2) 21 round magazines. The P320-M18...chosen by the U.S. Marine Corps and the U.S Military, now available to you for the first time.