I bought this battery case from China cost $15. It isn't MAKITA original battery case. It is 18V 9Ah battery case with PCB model BL18XXR1. I don't know why this PCB connected only 3 wires B-, B+ and B1. Let see how long the battery last. If you have experience with this, please share it with me in the comment section. - BL1890 Battery Case PCB Charging Protective Board Shell Box For MAKITA 18V BL1860 LED Li-ion Battery Indicator - PCB BL18XXR1 more detail in Google Lithium-ion battery cell - Brand model: LG INR18650HG2 - Standard capacity: 2800- 3000mAh - Rated voltage: - Charging voltage: 4.2± - Maximum continuous discharge current: 20A - Discharge cut-off voltage: - Weight: - Size: ×65.2 mm - Charge and discharge times: 500 times I hope you find this video useful and enjoy it! I am happy to receive feedback, suggestions to improve myself. !!! I'm sorry for the mistake if I did in this video !!! Thank you very much for your likes, comments, and subscription! Have a nice day Gear Show