The Blue Sea DC Digital Ammeter displays amperage on your marine equipment in large (9/16"H) LED characters that are easy to read in low light, at angles, and from a distance. Three levels of brightness. Splashproof front is suitable for marine environments. Manual sleep mode conserves power. Includes 500A/50mV external shunt. The standard meter only operates in the negative side of the circuit. A Shunt Shifter is required for positive side installation such as alternators. Easy spin-on mounting system for simple surface mounting with a 2" diameter hole or panel mounting with removable bezel. • Input Voltage: 8-32V• Power Consumption: 0.15 Watt minimum; 1.0 Watt maximum• Accuracy: ± 0.5%• Dimensions: 2.9"W x 2.43"H x 3.4"D 3 levels of display brightness Applicable for a variety of DC systems Includes 500A shunt | DC Digital Ammeter + Shunt, -500 to +500A