the slot and the screw holes are compatible with the 40-pin connector of the Raspberry PI
as well as the Raspberry PI Zero.

Compatible boards such as the Orange PI can also be attached. However, this has not been tested, so you should check the pin assignment beforehand to be on the safe side.

2 … + 5V input, from the DC / DC converter
3 … I2C SDA
4 … + 5V input, from DC / DC converter
5 … I2C SCL
6 … GND
8 … serial TxD
9 … GND
10 … serial RxD
14 … GND
20 … GND
25 … GND
30 … GND
34 … GND
39 … GND