Universal Adjustable Purple Manuel Turbo Boost Bypass Controller Kit 1-30 PSI In-Cabin Color: Purple Fits Most Turbo Vehicles. Perfect for Turbo-Charged Cars Running Between 0-30psi Increase or decrease boost pressure by turn knob clockwise or counterclockwise. Made with high quality CNC Machined and Anodized Aluminum 100% Brand New In Original Package Never Been Used. Come with Hardware. Professional Installation Recommended, No Instruction Included