Features: This battery capacity tester accurately monitors real time electric (V), current (A), power (), and battery capacity (mAh) for USB devices, providing essential insight into performances as a stable USB power meter. Featuring a high resolution LED display for clear data readability, a compact and lightweight plastic design for easy portability, and built in overload protect to prevent damage from short circuits and overloads. Ideal for enthusiasts, hobbyists, and professional who need to assess and maintain the battery performances of their USB charged electronics like smartphones and tablets. Perfect for everyday use in homes or office settings to meter and optimize battery health for devices including mobile phones, tablets, and easy carry power banks. With its general compatibility and user friendly interfaces, this electric tester offer a convenient and safe solution for monitoring battery position on the go. Specifications: Input electric ranges: 3V - 9V Input current ranges: 0 - 3A Length: about 72.2mm/2.84inch Package Includes: 1xCapacity Meter note: 1.Please allow 1-2cm errors due to manual measurement, make sure that you do not mind before you order. 2.Due to the difference between different monitors, the picture may not reflect the actual color of the item.