Super simple to install, simply connect the power you want to monitor! Some panel meters require a power source in addition to a sensor wire to the source you want to monitor. These units connect straight up, with no fuss! Suitable for use between 4.5V and 30VDC, they’re suitable for many DC applications including cars, boats, caravans, and other 12-24V sources. However their wide measurement range means they can be applied to many other applications too! Red coloured display. Panel mount with self-retaining spring clips.