Billet 50mm Sequential Blow Off Valve, this is the ultimate in high flowing billet valves - this valve will flow 800+ HP and utilises CNC fully machined components inside and out. This Valve is the best of the best, and will outperform some of the name brands on the market today - changes internally to this valve allow the response for various vehicle vacuum pressures to be dialed in perfectly without having the engine drop at idle or cut out at a stop.