The Stealth Project Muzzle Brake is 3 ports giving you maximum recoil reduction. The Muzzle brake geometry is machined to reduce carbon and copper fouling from getting in the threads. Designed to be used in conjunction with Stealth project STEALTH QD and RECON QD Suppressors, the front taper on the device self aligns with the suppressor to give you perfect alignment and perfect repeatability every time the suppressor is unattached and reattached. 1″-18 thread gives you quick attachment. Stealth Project muzzle devices gives you the longest attachment plane for you suppressor giving them the most rigid lockup. Muzzle device can be pinned and welded to make your 14″ barrel legal length to avoid SBR paperwork.