BOV boost pressure relief valve AMAZING SOUND EFFECT !!! It protects your turbo !!! Valve with complete bleeding of air into the atmosphere. The possibility of smooth regulation. The serial DV valve forces the air into the circulation, while the Blow Off valve - the atmospheric valve lets the air out, which protects your turbo, and at the same time produces an amazing sound effect - characteristic PSSSSSTT !!!! High quality. Dimensions: Inner diameter of the inlet: 28 mm Outer diameter of the inlet: 31 mm Outer diameter of the outlet: 28 mm Outer diameter of the vacuum nozzle: 4 mm BOV boost pressure relief valve AMAZING SOUND EFFECT !!! Protects your turbo !!! Valve with complete bleeding of air into the atmosphere. Possibility of smooth regulation. The serial DV valve forces the air into the circulation, while the Blow Off valve - the atmospheric valve lets the air out, which protects your turbo, and at the same time produces an amazing sound effect - characteristic PSSSSSTT !!!! 28mm Outer Diameter of Inlet: 32mm Outer Diameter of Outlet: 28mm Outer Diameter of Vacuum Nipple: 5mm