Built-in IC detects each cell voltage. And remember the number of uses!Detection battery status: Overheat, overvoltage, undervoltage, overcurrent, overcharge.Stable quality and anti-vibration. It is the best partner of Makita torque wrench and impact drill and angle grinder.Color: Blue, or Green, or Red, etc. any color, PCB color and version number are different according to the actual latest inventory.PCB design may change due to changes in the supply chain and processing technology.Note: If you have any objection to the following two items, please do not order !1. PCB color may be any color according to our stock.2. PCB design may change with the same function and performance guaranteed.Preparation before assembly:1. If a new core is used, please note:a. 18650 power lithium battery core must be selected.b. A group of six cores must be equipped with resistance and capacitance to make their voltage the same.2. If the old battery is repaired, please test the voltage at both ends of each cell. If the voltage is different, please charge each cell to the same voltage value.Very important:Ensure that the voltage of each cell is the same before welding PCB.Colour: picture colorMaterial: PCBPackage Contents:1 * PCB Charging Protection Circuit Board1 * LED BoardOnly the above package content, other products are not included.Note: Light shooting 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.