A nifty device to quickly indicate the condition of your 12V battery, charger or alternator. It uses 3 LEDs (12.6V Full, 12.0V 50% and 11.5V Low, to indicate battery condition), and 3 LEDs (15.5V Over voltage / Regulator failure, 14.5V Max. Charger Voltage, 13.2V Charger and Alternator Charging) to indicate Charger/Alternator output. Compact, lightweight, includes 600mm leads with croc clips, and inbuilt magnet to secure the unit while taking measurements.