OEM Russian made by Molot rifled 70mm paradox choke. Designed for Vepr 12 or Saiga 12 shotgun. Chrome lined. Both ends are threaded for installation of muzzle brake or flash hider, works great with Molot GK-01 and Lynx Kamerton. Rifled choke "paradox" are intended for shooting with specially made bullets for big game at a distance of 150 yards.