Features: 1. Onboard And Stable Esp07 Wifi Module, Large Capacity 4m Flash 2. The I/0 Port Of The Wifi Module And The Uart Program Download Port Are All Lead Out To Facilitate Secondary Development; There Are 4 Channels Of 5V Relays On The Board, Which Output Switching Signals And Are Suitable For Controlling The Working Voltage. Loads Within AC 250V/DC30V 3. Onboard Ac-Dc Switching Power Supply Module, Power Supply Mode Supports AC90-250V/DC7-30V/5V 4. Onboard Wifi Module Reset Button; Onboard Power Indicator Light, 1 Programmable Led And Relay Indicator Light 5. ESP07 Supports The Use Of Development Tools Such As Eclipse/for Arduinoide And Provides for Development Reference Procedures In The Environment Description: Product Name:Relay Module Board Size: About 93 x 87mm Material: PCB colour: As shown Package Contents: 1 x Relay Module 1 x 6Pin Double Row Pin 1 x 6Pin Single Row Of Pins 1 x 4Pin Single Row Of Pins 5 x Short Circuit Cap Only the above package content, other products are not included. Note: Light reflection 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.