Enhanced version: for starting current below 80A, power 135W below the drill.(Not balanced function) 3S 12.6V 40A lithium battery protection board Scope: Nominal voltage of 3.6V, 3.7V lithium battery (including 18650,26650, polymer lithium battery) Product Size: 42 * 55 * 3.4mm (Standard Version / Enhanced Version), 42 * 60 * 3.4mm (Balanced version) Product weight: 8.8g (standard / enhanced version), 9.8g (balanced version) Charging voltage: 12.6V - 13.6V Continuous discharge current (upper limit): 40A (if the cooling environment is not good, please reduce the load current use) Continuous charge current (upper limit): 20A Note 1: The successful start of the drill requires three 15C-20C power battery, or six 10C-15C power battery (ordinary 18650 can not start the drill!!). Note 2: strictly according to map wiring 0V, 4.2V, 8.4V, 12.6V, do not deliberately short circuit. Note 3: When the load of the brush motor is used, try to connect a non-polar capacitor (withstand voltage above 25V, capacity 10uF-100uF) to the motor's positive and negative terminals to prevent the reverse spike from the motor. Break the MOS tube. Note 4: 3 groups of batteries in series, please ensure that the voltage of each group of batteries, if not the same, please fill each battery separately and then use in series. The The Discharge test, the voltage drop faster battery that group is poor battery. For some of the poor basis of electronic customers to explain: balanced charge is only auxiliary functions, try not to put a good battery and poor battery mixed together! 3 sets of battery capacity / resistance closer to the better! (2 good battery +1 Poor battery use effect = 3 poor battery use effect).