No Cell, PCB Board Circuit Board for Milwaukee 12V Li-ion Battery. No Battery Cell! Intended for repairing and assembling battery packs. For individuals familiar with battery performance and experienced in battery assembly. 1. What should be considered when assembling a tool battery pack? Use consistent 18650 power cells in model, voltage, and internal resistancebetter consistency ensures optimal performance. The voltage detection line must be properly connected. It is recommended to use new batteries rather than recycled cells. A spot welder is required. 2. When replacing the protection board: Before installation, measure the voltage of each 18650 cell group to ensure uniformity. The protection board provides safety functions only and does not balance voltage. If the battery pack has uneven voltages, charging or discharging may fail. Replacing the protection board will not resolve voltage imbalance. Use high-quality 18650 batteries. Please note: If you disagree with any of the following, do not purchase: (1) PCB color may vary based on available stock. (2) PCB design may be updated while maintaining the same function and performance. (3) Component count and placement on the PCB may vary while ensuring full compatibility. Note: Due to different production batches, silk screen markings and appearance may vary. This does not affect functionality. Color: Random (no color selection available) Material: PCB Package Contents: 1 x Li-ion Battery Protection Board