Features: 100% brand new and high quality It can hold 10 18650 lithium ion batteries. But this is only a plastic case, there is no battery inside. If the old batteries are repaired, please test the voltage across each battery. If the voltage is different, charge each battery to the same voltage value. Make sure that the voltage of each battery is the same before soldering the PCB. This is just a battery box, there is no battery inside, suitable for DIY use of 18V lithium ion batteries, customers should know how to assemble. The box we provide is by your side. Otherwise, if you don't have enough assembly skills, please don't place an order. Please know in advance. Package Includes: 1x Li-ion Battery Case Specifications: Material:ABS Net Weight:180g note: Please allow 1mm errors due to manual measurement. Due to the difference between different monitors, the picture may not reflect the actual color of the item.