Input: Optional type-c port or solder input. Type-c connected to Qc fast charging can automatically adjust the charging voltage and improve charging efficiency. If solder input is used, the input power supply should be less than the battery voltage (battery series number * battery voltage)Output: Supports 2 and 3 strings. The battery needs to be equipped with a protective board, with a default of 2 strings. When changing to 3 strings, the short circuit contact needs to be short circuited, and then the adjacent resistor needs to be removed. Two strings can use the balancing function, with two strings of batteries connected to the BM pin in the middle (this balancing speed is limited, so when using the two strings of batteries, it is still necessary to that the parameters are consistent as much as possible) Current setting: The green in the above figure indicates that the default current settings for two parallel connections are 100K (0.9A) and 180K (0.5A). Resistors can be removed or replaced according to personal needs. The calculation formula is current=90000/resistance value. The cut-off voltage for battery charging is set to 4.2V by default for a single string, which is also the same value for most batteries and does not need to be changed. If changes are needed, refer to the RVSET settings table to set the board VSET resistance. Charging timeout setting, default no timeout time, set the ROT resistance value to set. 68K-4 hours, 120K-12 hours, no stickers -24 hours connection: Not used normally. If necessary, change the NC resistance value to 82K, and connect a 100K thermistor (B=410) to the soldering point and adjacent GND Colour:Black Material:PCB type:2S Package Contents: 10 x Boost Module Only the above package content, other products are not included. Note: Light reflection 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.