12 - 24 VOLT PLUG-IN TESTER W/USB
PLUG-IN LCD DIGITAL BATTERY TESTER with 2x USB CHARGE PORTS
The 12 and 24 Volt Cigarette Lighter Plug-in Digital Battery Tester monitors the voltage of the battery, tests how much life is left in the battery, features an audible alarm when the battery's voltage drops below 12.0 Volts, checks the power output of your alternator and has a red/blue light indicator which shows if the battery is good or bad. This device is entirely plug and play.
PLEASE BE AWARE: Some vehicles shut off power to the cigarette lighter port once the vehicle is turned off and the keys are removed from the ignition.