With a balanced, same port 45A/80A discharge. Protection board with overcharge protection, over discharge protection, over current protection, short circuit protection, temperature protection. Accessory Type: Charger Accessories Model Number: BMS 20S 72V 45A/80A 18650 Lithium Battery Protection Board Attention when connecting: When we connect BMS with cells or disassemble BMS from battery pack, the following order and regulations must be complied with to avoid damage of components of BMS and problems of not protecting of cells. In order to achieve the performance of BMS and to run the distance, all the battery must be matched well (Each battery voltage less than 0.05V, IR less than 15 m,capacity less than 30mAh) to make the better consistency of the battery. Cell must be connected in parallel first, after then connected in series Order of connection: Step1: Connect charging /discharging wire , battery pack negative wire Step2:After confirm the wires are connected OK, plug the connector cable in the BMS DO NOT plug CONNECTOR CABLE in the BMS connect wire!! Attention, ESD protection during work. colour:Silver Material:Metal + plastic size:120 x 60 x 10mm Package Contents: 1 x Battery Protection Board 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.