Scope: Nominal voltage of 3.6V, 3.7V lithium battery (including 18650,26650 polymer lithium battery) Charging voltage: 16.8 V-18.1 V Continuous discharge current (upper limit): 40 A (if the cooling environment is not good, reduce the use of charging current) colour: green Material: plastic +metal size: 54x44x4mm Package Contents: 1 x 4S 40A Li-ion Lithium Battery Protection Board Note 1: The successful start of the drill requires three 15C-20C power batteries, or six 10C-15C power batteries (the normal 18650 cannot start the drill!). Note 2: strictly in accordance with the map wiring 0 V, 4.2 V, 8.4 V, 12.6 V, 16.8 V, do not intentionally short circuit. Note 3: When using the brush motor load, try to connect a non-polar capacitor (withstand voltage above 25 V, CAPACITY 10 uF 100 uF) to the positive and negative terminals of the motor to avoid the reverse peak of the motor. Break the MOS tube. Note 4: 4 groups of batteries in series, make sure that the voltage of each group of batteries, if not the same, complete each battery separately and use it in series. The discharge test, the battery voltage drops faster than the group is a poor battery. Only the above package content, other products are not included. Note: Light shooting 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.