EverStart 16 foot 6 gauge Smart Booster Cable, Jumper Cable, Battery Voltmeter, Reverse Polarity Warning.Smart Feature Instructions: How to use the Voltmeter for checking polarity before Jump Starting an Engine: 1. On the car with the dead battery, connect the red clamp to the positive battery post and the black clamp to the negative battery post. 2. If the connection is reversed, the Wrong Polarity Indicator (RED) LED will light & flash, and an alarm will sound. If the connection is correct, no alarm sound or RED LED light, the Voltage Indicator will light and battery’s voltage* will be detected and displayed on the digital screen. 3. Disconnect the black clamp from the negative terminal of dead battery in order to reactivate the Voltmeter to proceed step 1 & 2 for checking the working battery. WARNING : The reverse alarm and LED light only work when detecting battery voltage on the first vehicle. If clamps are reversed on the second vehicle’s battery without step 3 above, sparking may occur and cause damage on the batteries or engine. * When connected to both vehicles, the voltmeter will display the average voltage of both batteries.
