This Clutch-Lok QD mount doubles as a muzzle brake for 7.62MM SLH/SLX suppressors. It offers a quick and simple attachment of suppressors and less felt recoil when the suppressor is removed. Shoulder interface: 90-degree taper for use with SIG SAUER Taper-Lok barrels. Model Clutch-Lok QD Series Muzzle Brake Material Stainless Steel Thread Pattern 5/8"-24 tpi