Compression Tester Tool Type Compression Tester Testing Application Cylinder Compression Material Rubber Number of Pieces 3 Features Adapters Fit 14 and 18 mm Spark Plug Holes and Special Air-Hold Valve Checks Cylinder Compression from 0 to 300 psi and 0 to 21 kg/cm2 Limited Lifetime Warranty Includes 14 mm and 18 mm Adapters 16 in Rubber Hose Test Gauge Overall Length 11 5/16 in Overall Width 3 11/16 in Compatible Vehicle Part Cylinder