This QuickCar Gauge is a Water Temperature unit from the Extreme Gauge Series and features the QuickCar Logo. A 12 or 16 Volt power source is required to power gauge. Display has a 140-280 F Range and face is a 2-5/8" Diameter. A water temp sender, 61-740 purchased seperately, must be installed to make gauge change colors when temp rises about 240 degrees. This is Mechanical type gauge with a 6 Foot capillary tube on the backside. Sold each.