Iztoss WATERPROOF Voltmeter 12-24V DC green LED Digital Display voltage meter socket Universal for Automobiles Motorcycle Truck Boat Marine Sold from Iztoss,send 2 wires and opening drill for free Measure voltage: 6 - 30V. Measuring DC voltage, positive and negative connections,with anti-reverse, short circuit protection. Universal fits for 12V-24V Vehicle, Motorcycle, ATV, Boat, Car or Marine. Mounts in a 1-1/8" hole in panels up ,0.25" thick, a nylon retaining nut holds the meter in place.