Features: 1.Easy to measure the USB output vollage and the device input current or loader voltage. 2.Availabe for every USB electronic product,such as PC USB,home charger,car charger and so on. 3.Plug and ,light and handy,easy to carry and no need external power. 4.Through "DR CHARGER",you could clearly know the condition of the charger ,phone,usb cable and every USB device. Detection range: Voltage:DC 3.5V-7V,error 0.1V Current:0-3.0A,error 2% Features: 1.Easy to measure the USB output vollage and the device input current or loader voltage. 2.Availabe for every USB electronic product,such as PC USB,home charger,car charger and so on. 3.Plug and ,light and handy,easy to carry and no need external power. 4.Through "DR CHARGER",you could clearly know the condition of the charger ,phone,usb cable and every USB device. Detection range: Voltage:DC 3.5V-7V,error 0.1V Current:0-3.0A,error 2% Features: 1.Easy to measure the USB output vollage and the device input current or loader voltage. 2.Availabe for every USB electronic product,such as PC USB,home charger,car charger and so on. 3.Plug and ,light and handy,easy to carry and no need external power. 4.Through "DR CHARGER",you could clearly know the condition of the charger ,phone,usb cable and every USB device. Detection range: Voltage:DC 3.5V-7V,error 0.1V Current:0-3.0A,error 2% polybag