6 mm x P1.0 mm Carburetor Adapter Set by Motion Pro®. Quantity: 4 Short. Precise 4-channel vacuum indicator designed specifically for intake synchronization of engines with multiple carburetors or throttle bodies.New mercury-free designIncludes manometer fluid, hoses, 5 mm adaptors, in-line restrictors and instructionsPrecisely engineered to ensure ultimate efficiencyManufactured using innovative technologiesAbsolute quality, great durability, and solid workmanshipIncludes:4 Pieces Short