KD Tools 2521 KDT-2521 Fuel Pump Vacuum and Pressure TesterTest for fuel line pressure and vacuum leaks and check for leaky valves,"timing, fuel pump vacuum and pressure and gas line leakage. Testeris equipped with an easy-to-read gauge with a 3_ hose and a vacuumhose adapter fitting. Gauge measures vacuum from 0 to 28_ Hg in 1_increments (0 to 700mm Hg in 50mm increments). It also measurespressure from 0 to 15 psi in 1/2 psi increments (0 to 1 kg/cm2 in 0.1kg/cm2 increments). Gauge diameter 2 11/16_.Caution: Not for use on fuel injected vehicles.