Pin interface compatible with standard spacing Arduino Uno, Mega, etc.    
3.3V power supply chip (same with the official expansion board power chip CC3000 ).    
Onboard ESP8266-12 stable industrial grade serial WiFi module, using an enhanced PCB antenna    
Can switch by DIP switch ESP8266-12 stable industrial grade WiFi module operation mode (such as operating mode and upgrade mode), integrated serial port chip    
Built-in 5V to 3.3V TTL level converter,    
Onboard standard pitch leads all interfaces ESP8266-12 stable industrial grade WiFi module    
Onboard four LED displays the status of ESP8266, namely PWR, DFU, AP, STA