1. Onboard mature and stable ESP-12F WiFi module, large capacity 4M Byte Flash.2. The I/O port and UART program download port of the WiFi module are all led out, which is convenient for secondary development.3. The power supply mode supports DC7-28V/5V.4. Onboard WiFi module RST reset button and a programmable button.5. ESP-12F supports the use of development tools such as for Eclipse/Arduino IDE, and provides reference programs in the Arduino development environment.6. Onboard 8-way 5V/30A relay, output switch signal, suitable for controlling and controlling loads whose working voltage is within AC 250V/DC30V.7. Onboard power indicator, relay indicator and 1 module comes with LED.8. Two onboard shift registers 74HC595 control the relay switch.Type: Relay ModulePower supply mode: DC7-28/5VRated current: 30A3C rated voltage range: below 36Vcolor:blueMaterial:PCBsize:150 x 100mmPackage Contents:1 x Relay ModuleOnly 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 +/- 1-3cm.