Product selling points: 1. Simultaneous display of voltage and current mAH data, easy to view can detect mobile power output mAH 2. Multi-group detection data preservation, power failure preservation function does not affect data transmission 3. Higher precision, current parameters will not jump basically current sampling 25 mOhm loss smaller 4. With precision current calibration function, higher current accuracy 5. Safe charging, real-time monitoring and control of your charging data Input voltage: 4-30V Voltage resolution: 0.01V Test current: 0-3A Current resolution: 0.01A Capacity range: 0-19999mAH Accuracy: plus or minus 1% Line loss: about 0.1 ohm Test content: battery voltage, current, discharge capacity (10 sets of data in total) Tips: The product may be updated constantly, Due To Different Batches, The Actual Product May Have Slight Differences Or Color Differences, Which Does Not Affect Use Material: plastic colour: B-White Package Contents: 1 x Voltmeter Tester Meter Only 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.