ATC Unique Automotive Compression Tester Kit Cylinder Compression Checks 0 to 300psi Fits for 14mm & 18mm Spark Plug Treads 13" Flexible Hose 2-3/4" Diameter Gauge for Easy Reading, Air-Hold Valve & Gauge Reset Button, Universal Rubber Cone Adapters Which Fits All Plug Holes,6" Heavy Duty Stem