The 3.9" barrel has a clean bright bore with strong rifling. The P320-M18 is the commercial version that brings the same unprecedented accuracy, extreme reliability and unmatched durability the military demands in a compact carry pistol. 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 (3) 10 round magazines.