Discover the Sylvan Arms muzzle devices that come in 5/8 x 24 or 1/2 x 28. Made out of 17-4 SS for durability and long life. They are designed to work with the Sylvan Arms 30 Cal and 223/556 suppressor lines. The 5/8 x 24 fits the 30 cal can while the 1/2 x 28 fits the 223/556 can. The muzzle device can also be used as a Flash Hider. Easy to install, simply screw the Flash Hider onto your appropriate size barrel and tighten with an armorer wrench, No washer is needed.