High temperature protection for charging and discharging, low temperature charging protection.Temperature control parameters are externally adjustable. Overcharge detection protection.Three stage overcurrent protection.Externally adjustable during the first and second stages of overcurrent delay. Battery disconnection protection function.NTC resistor disconnection protection function.Suitable for (for Makita) chargers.This product is component without battery core. It is used to repair and assemble batteries pack,only for people who are familiar with battery performance and have practical experience in battery assembly.<br><br>Precautions for use and assembly: 1) When welding battery leads/sampling points, be careful not to connect them incorrectly or in reverse. If a wrong connection is found, the circuit board may have been damaged and needs to be retested before it can be used again. 2) During assembly, the BMS should not directly contact the surface of the battery cell to avoid damaging it. The assembly should be firm and reliable. 3) Electronic devices used for welding must be reliably grounded, and attention should be paid to electrostatic protection to prevent damage to the protective board caused by electric leakage and static electricity 4) Be careful not to touch the components on the circuit board with lead wires, soldering iron, etc. during use, otherwise it may burn out the circuit board. The appearance color of some accessories is random, don't accept the specified color; which does not affect the use, and the actual product does not include batteries Colour:Black Material:Metal+Plastic<br><br>Package Contents: 1x BL1890 Li-ion Battery Case set<br><br>Only the above package content, other products are not included. Note: Light reflection 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 +/