18x1 To .578x28 Thread Adapter For 9mm Cz Scorpion

18X1 to .578x28 Thread adapter for 9mm CZ Scorpion EVO 3 S1 pistol & Tikka Sporter. This adapter will enable the use of a more common threaded muzzle brake, compensator or suppressor. Machined steel, finished in durable black oxide with machined wrench flats. OD is .88"