The ESP8266 Wi-Fi 5V 2 Channel Relay Module IOT Smart Home Remote Control Switch uses ESP-01 as the Wi-Fi module and is compatible with 8 bit MCU chips. Only a simple configuration process can realize the wireless control of the 2 way relay by using the mobile phone APP in the LAN Onboard high performance microprocessor STM8S103 and ESP-01 Wi-Fi modules. The module has 2 operating modes of work: Mode 1: Mobile phone is directly mounted on Wi-Fi module. Mode 2: Mobile phones and Wi-Fi modules are equipped on routers simultaneously Additional function: It can also be used as USB relay when ESP-01 is pulled out. Transmission distance: In an open environment, the maximum stable transmission distance is 100M when the mobile phone is mounted on the Wi-Fi module. When the Wi-Fi module and mobile phone are carried on the router at the same time, the transmission distance depends on the signal strength of the router. The use of Smartconfig technology in the mobile phone on the APP ESP-01 Wi-Fi module to complete the account and password configuration, configured username and password memory function. Onboard 5V, 10A//250V AC 10A//30V DC relay, which can be continuously pulled for 100 thousand times, has diode discharge protection, short response time. Board mode selection and real time working status indicator. Reserved UART debug interface and STM8 SWIM program download interface.