Evolution Gun Works AR Comp Post-Ban Gen II muzzle device with a 0.900 diameter and 1.75 length. AR-15 muzzle compensator, finished in black steel with Peel Washer for installation. Available in 1/2-28 and 1/2-36 thread patterns for rifle and carbine configurations; bore options include .223 for compatibility with .223 Remington; custom bores may require about two weeks lead time. Package contents: Evolution Gun Works AR Comp Post-Ban Gen II, .900 in.