Mechanical Boost/Vacuum Gauge;Incl. 6 ft. Tubing; California Residents: WARNING The standard in the industry, Auto Meters Mechanical Boost/Vac Gauges have found their way into more builds than any other. Using a patented, high precision bourdon tube meter movement, there is not another gauge on the market that can lay claim to the levels of accuracy or durability you will find here. A simple 1/8 inch NPT pressure connection requires no electrical hookup for operation. Includes 1/8 inch NPT fittings and nylon line kit.