Davtron’s Model 451 voltmeter is a small, lightweight instrument that monitors the voltage of your aircraft precisely. The pilot can more accurately know the amount of capacity remaining in the battery when there is a low voltage condition. Also of great importance is the voltage at which the battery is being charged. Overcharging can lead to excessive water loss and battery failure. Model 451 is an extremely useful instrument which helps the pilot get better and more reliable service from the electrical system.