PARAMETER -- measuring voltage DC 4.5V-100V; current 0-50A. APPLICATION -- monitoring storage battery, solar panel, model railroad, RV, motorcycle, house batteries, motor, etc. DISPLAY -- 0.39'' crisp and bright LED screen displays voltage & current value. CALIBRATION -- with voltage & current calibration potentiometer. NOTE -- the shunt should be connected when wiring, otherwise the meter will be burnt.