M2 DC Ammeter, measures 2 circuits. Supports programmableshunt ratios. Auto-dimming, bright organic LED display is easy to read80dB alarm on all modelsIsolated 500mA MOSFET relayIncludes external DC shunt or AC current transformer when requiredDisplay Size: 55mm x 28mmPower Supply Voltage: 7-70V DCRange (Power Consumption): 0.3W - 1.0W Variable with voltage, display intensity,and sleep mode