Onewell LCD USB Charger Computer Battery Capacity Power Current Voltage Tester Meter J82 Display Current (Amps), voltage and capacity (99,999 mah);Input Votage:3.0-15V; Input Current:0-3.5A; Voltage Accuracy: when 3.0-15V, 1%; Current Accuracy: when 50-3500mA, 1%; Maximum Capacity Value: 99999 mAh; Maximum Save Data Group: 9 Dual USB Port Voltage Amp Meter: Support 2.0 quick charge monitoring. Two USB port can be used simultaneously. USB1 Port: For charging, contain CW3002D chip for universal USB fast charging adapter features; USB2 Port: Data Transmission and also for charging Test using a USB charger, battery power bank, micro USB cable or computer. Support to test your iPhone or Android phone Automatically protection: The buzzer will alarm when the device is over voltage and over current. The USB port will be shut down automatically to protect the device Important Notice: Input Voltage must not over 15V, or the monitor may be pernamently damaged. Power supply voltage must be 4.6-15V.If you use "USB load resistance" must not work for a long time during electric current over 3A (12 Month Warranty)