Conventional voltmeters are very good at showing how many volts there are in your electrical system. While this is a good enough indication of your electrical systems operation, a voltmeter is all but useless when you need to know just how much energy is left in your battery. A Battery Condition Indicator eliminates all the guesswork. The expanded scale accurately displays the battery’s usable energy, telling you when to recharge.. even when it’s time to replace your battery. A must where one or more batteries are used. The Faria Battery Condition Indicator is an accurate and inexpensive solution for knowing exactly how much power remains in your battery.