1. ESP-12F WIFI module and stable onboard, large flash capacity of 4M bytes. 2. The WIFI module input/output port and UART program download port are all led out to facilitate secondary development; 3. Onboard WIFI module reset button. 4. ESP-12F is compatible with development boards such as for ECLIPSE/IDE. 5. 2 to 5V relay, output switching signal, suitable for controlling AC load operating voltage within 250V / DC30V. Onboard power indicator, 1 programmable LED and relay indicator. Color: Green Material: PCB Size: 78x47mm Package Contents: 2 x ESP8266 ESP-12F WIFI Relay Module 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 +/- 1-3 cm.