Available in gasoline and diesel models, Digital Compression Test Kits feature backlit LCDs that show measurements in psi, Bar, or kPa. They provide memory storage of peak readings on up to 12 cylinders, and values are retrieved by scrolling through cylinder numbers. Construction features grease- and oil-resistant gauge face as well as buttons that are sealed from elements. Timed automatic shutoff feature helps extend life of 9 V battery.