Sonoff Mini R2 – small WiFi smart relay switch with DIY mode
Sonoff R3 DIY mode & why it sucks - NotEnoughTech
Make your own Sonoff | DIY Sonoff | Sonoff wifi switch using ESP8266 and MQTT | IoT Projects - YouTube
SONOFF MINI – Two Way Wi-Fi Wireless Smart DIY Switch Turn traditional switch to Smart WiFi Switch With Timer Internet Work With AMAZON Alexa,google Home ,Nest – Sonoff India