It's for 8 Pin NRF24L01+ Module
A simple socket board which is for NRF24L01 wireless module
On-board AMS1117-3.3 chip
It can be used with NRF24L01 wireless module
Dimension: 26 x 19 x 12mm
Wireless module operating voltage is generally 3.3V, while the ordinary 51 microcontroller 5V, this module is wireless module with 51 single system board used in conjunction.