Brand New, No Battery Cell! BAT411 BAT420 Plastic Case ( no battery cell ), PCB charging Protection Board and 6Ah Sticker For 10.8V 12V BAT412A BAT413A Li-ion Battery. 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. Lithium battery shell sleeve is suitable for 10.8V12V BAT411 lithium battery, it can fill 6 pieces of 18650 li-ion batteries. But this is only a shell, there is no battery inside. 1. What should be paid attention to when assembling pack? 18650 power cell, model, voltage, internal resistance should be consistent, consistency is better, 10.8V 3 strings, 14.4V 4 strings, 18V 5 strings. The voltage detection line must be connected to the detection line. Try to use better batteries instead of dismantling the electric core. Need spot welder. 2. When the protective plate is used to replace the original Before changing the protection board, be sure to measure the voltage of each group of 18650 cells to that the cell voltages are consistent. The protection board only plays a protective role and cannot balance the voltage. The battery cannot be or discharged due to the inconsistent voltage of the battery pack. It is useless to replace the protection board. It is recommended to use new 18650 batteries. Colour: black Material: plastic Package Contents: 1 x Li-ion Battery Plastic Case with 6Ah Sticker Note: The color of the protective plate is random, don't accept the specified color, and the battery is not included Only the above package content, other products are not included. Note: Light 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.