1. Full automatic power off - turn light function: When the battery is fully , the circuit will whether the battery is fully , so as to cut off the power supply to prevent explosion caused by overcharging2. Due to different smartphone manufacturers, the battery interface of the mobile phone is common, the output and negative poles are different, and the power supply is opposite. This product can automatically identify the and negative poles of the battery.3. In the process of repairing mobile phones, it can supply power through the USB link, and accurately detect the voltage and current values of the charger, and can measure the power supply and power consumption of the USB interface, U disk, etc. It can measure the voltage of the USB power supply device when it is empty/loaded, and the load current of the USB terminal device when it is working.4. The design protection current of this product is not more than 2A. When the high voltage is accidentally connected, the protection board will automatically cut off the power supply to avoid unnecessary losses. It will resume normal work within 1 after disconnection.Instructions for use:Battery charging: Charging or activating the built-in battery - first connect the small board to the power supply, then buckle the battery on the activation board to charge.Battery activation: Activate the built-in battery - Some batteries in mobile phones have been placed for too long and cannot be . At this time, you need to use this board to activate they can be normally. Connect the small board to the power supply and directly buckle the battery on the corresponding buckle , press the activation button once to activate.Colour:blackMaterial:PCB+electronic componentsPackage Contents:1 x Battery Charging Activation Board1 x CableOnly the above package content, other are not included.Note: Light reflection and different displays may cause the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm.