It is a Digital Ammeter/High Accuracy Digital Tester, Operating voltage: DC +5 V +/- 0.5, Measure Current Range: DC 0 ~ 50A ( require external 50A shunt ), It has Reverse polarity protection, small size, high efficiency, long term stable and reliable quality,easy installation and use. Application: industrial equipments,electronic equipment, Power distribution box, distribution cabinet, regulators, teaching aids and All kinds Current Measurin