Features: UT658 USB tester is used for quality testing of electronic chargers, power banks and other charging equipment. It is designed to improve the charging efficiency and to protect charging equipment. It can measure voltage 3.0V~9V, and measure current 0.0A~3.0A, with measurement precision of ±1%. Different data displayed on one screen, real-time monitoring, safe and reliable. Smart memory of charging capacity, quick testing for power bank s. Specifications: Brand: UNI-T Model: UT658 Function Specifications Description Input voltage range 3V~9V 'OL' is displayed when greater than 9V Voltage Resolution 0.01V Voltage monitoring accuracy ±1% Current monitoring range 0A~3A 'OL' is displayed when greater than 3A Current monitoring accuracy ±(1%+2) ±(1%+3) when less than 500mA Voltage resolution 0.01A Capacity 0~9999mAH Portable battery capacity Capacity data storage 10 sets Display method LCD With backlight Sound alarm/Warning Yes When higher than 5.3V or less than 4.7V Key Function Yes Pollution Level 2 Operating temperature 0℃~40℃ Storage temperature -10℃~50℃ Relative humidity <75% Size 8.3*2.5cm/3.3*1in Weight 32g (approx.) Note: 1, There might be situation that provided data is limited depending on testing different products. 2, If current is less than 0.05, it will display 0.00. 3, It might not test accurately for equipment which has quite low power consumption, such as energy-saving designed mouse, keyboard, hard disk. 4, If the tester is connected to computer alone, it will show voltage value only. 5, The tester itself also will cause certain current loss, so the data displayed is the sum of equipment and its own. Package Includes: 1 x USB Tester