The Griffin Armament PSR (Precision Suppressor, Rifle) DUAL-LOK 2 Port Muzzle Brake is a precision DUAL-LOK muzzle device made specifically for the DUAL-LOK PSR suppressors. PSR (Precision Suppressor, Rifle) over the barrel suppressors provide unprecedented blow back reduction, sound performance, and accuracy. The PSR DUAL-LOK 2 Port Muzzle Brake is equipped with two rearward directing recoil reducing ports, with vertical compensation slots, the two port brake provides flat shooting performance in addition to maximum braking power. Also incorporated into the muzzle device, a taper surface to ensure solid lock up and minimal/repeatable POI Shift. The muzzle device integrates 60 machined mounting position locking grooves, which is doubled by the mount's two locking positions, hence the double entendre DUAL-LOK. How is this achieved? The mounts' two locking positions are machined out of phase of one another by 3 degrees which provides the 120 effective locking positions an...