Designed to test the electrical system of an automotive vehicle running on 12V or 24V. It is able to activate components with positive or negative without using a jumper wire, which would for example, allow you to send voltage to a relay that controls whether or not a fan switches on. You can quickly test the voltage and polarity of a circuit or whether it's short or open, check continuity, locate cylinders which are misfiring, measure frequency of ignition pulses, test solenoids, lights and more. To top it all off the easy to read LCD is backlit so it's perfect for the dark crevices of an engine bay. Works on 12 or 24V systems Dimensions: 240(L) x 78(H) x 40(W)mm Specifications Led Indicator Display : true Display Type : LCD Display Backlight : LED Backlit DC Voltage Ranges : 12V Connection to meter : Hard Wired Height : 78mm Width : 40mm Length : 240mm DC Voltage Ranges : 24V Packaged Length : 30.2cm Packaged Weight : 0.4kg Packaged Height : 6.9cm Packaged Width : 7.3cm Packaged Volume : 1.52l