Product description:SonoffT0EU3C-TX - Touch Wall Switch - WiFi - 3 channel. Intelligent wall-mounted light switch fromSonoff, allows you to control the lighting with the touch fields on the switch and for more advanced, customized control with a phone application, lighting management is done through 3 control channels.The T0EU3C-TX switchis a newversion of the already known Sonoff T0 switch. In simple terms, a Sonoff device contains an ESP8266 chip connected to a relay. This way you can connect to the Sonoff via Wi-Fi to control the relay. The sonoff comes with a firmware that allows you to control it using the eWeLink app. However, most people prefer to flash the Sonoff device with custom firmware as we'll do in this project. Sonoff Basic Wifi R3. This is a WiFi Smart Switch with the DIY capability that makes it possible to control connected devices via the eWeLink directly from your phone, or ask it to turn on/off devices with Amazon Alexa and Google Assistant. Amazingly, it has a DIY mode that is the firmware can be user-defined.