Working voltage of Meter: DC 4 - 30VWorking current of Meter: less than equal 20mAVoltage Measuring range: DC 0 - 100VCurrent Measuring range: DC 0 - 10AVoltage resolution (V): 0.1VCurrent resolution (A): 0.01AMeasure accuracy: 1% ( 1 digit)Display: 0.28inch digital tube, Two color blue and redRefresh rate: about 300mS / timesDimensions: 48mmx29mmx21mmOperation Temp: -10-+65Note:The maximum input voltage can not exceed 30V. Otherwise the meter will be burned out.colour:blackMaterial:ABS + electronic componentsPackage Included:4 x 0.56inch Digital Voltmeter Ammeter DC 100V 10A Blue + Red LED Display4 x Set of two wiresOnly the above package content, other products are not included.Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.