Accurately displays the total percentage of leakage past the rings, head gasket, intake and exhaust valves. Meets FAA leak down test specifications for cylinders below 5.00" (127 mm) bore diameter. Tests at 80, psi cylinder pressure and requires 90 PSI air source. Hose and adapter fits 10 mm, 12 mm, 14 mm spark plug threads. Speeds up troubleshooting and helps to isolate bad components. Precision digital display provides accurate, easy to read results. Easy to use precision pressure regulator built into body of tool. Includes convenient molded tray and instructions. Rugged rubber boot protects digital gauges. Includes 1/4" male industrial quick connector.