OEM Russian made by Molot cylinder choke. Designed for Vepr 12 or Saiga 12 shotgun. Both ends are threaded for installation of muzzle brake or flash hider, works great with Molot GK-01 and Lynx Kamerton. Half choke - reduction 0.5. Gets 55-60% group accuracy. As half-choke, suitable for firing any size pallets. Round bullet must pass freely through the choke.