BOV:Accessories: Flanges, bolts and gaskets are included. All our BOVs are thoroughly tested to make sure the valve ... servicing life of springs and diaphragms used for the BOV lasts for 200, 000 times of operation (open ... under 200C (or 392F). Materials used for making BOV are high quality aluminum alloy.All our BOVs have ... Accessories: Flanges, bolts and gaskets are included. Blow off valve(forge bov)