Griffin Armament is proud to offer the GATE-LOK mounting system as a 1.375x24 threaded interface. The GATE-LOK mounting system is one of the fastest on the market and accommodates the A2 NATO compensator as well as Griffin's GATE-LOK series proprietary performance rich muzzle device options. Additionally the GATE-LOK mounting system does not suffer from the wear prone issues of ratcheting systems common to the marketplace. This mounting system was designed to provide trouble free use. FeaturesLaser WeldedExtremely versatile and fast mounting systemCompatible with GATE-LOK(TM) & A2 Nato Spec Compensators17-4 stainless steel DLC PVD for increased surface hardness, corrosion, and wear resistance Compatible with:GATE-LOK Closed Tine Flash Hider 5.56mm 1/2x28GATE-LOK Hammer Comp 5.56mm 1/2x28GATE-LOK Stealth Flash Hider 5.56mm 1/2x28GATE-LOK Flash Comp 5.56mm 1/2x28GATE-LOK Flash Comp .30cal 5/8x24