1. A power management system with a core processor; 2, can display the battery voltage (to prevent the use of batteries that are deficient in electricity, can not reach the of continuous battery replacement); 3, can display the current (can be used for leakage detection, can also understand the quiescent current of the car in the non-start state); 4, battery clip anti-reverse protection (the digital tube does not light after the reverse connection, no power); 5, over-current protection (with 5 amp insurance); Voltage and current are automatically cycLED. Four major functions: 1, continuously change the car battery; 2, car leakage detection; 3, display voltage; 4, display current; Three major protections: 1. Battery loss protection; 2. Battery clip anti-reverse protection; 3. Overcurrent protection; Three major instructions: 1. Connect the positive and negative poles of the battery clip correctly. The digital tube will and display the value. If it is reversed, the digital tube will not . 2. If the OBD interface is properly connected, the red LED will , if the connection is unsuccessful, the red LED will not ; 3. Voltage and current switching instructions. The Bluetooth LED is on, indicating that the current digital tube is displaying current data, and the blue LED is not lit, indicating that the current digital tube displays voltage data. Battery change process description One: The battery clip is reliably clamped on the positive and negative poles of the spare battery (the red clip is connected to the positive pole and the black is connected to the negative pole). If the connection is correct, the digital tube will display the number (Bluetooth LED is on - display current, blue LED is off - display voltage). Color: Transparent Material: ABS Package Contents: 1 * OBD Battery Replacing Tool Only the above package content, other products are not included. Note: Light 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.