1pcs ESP8266 WiFi Relay Module with ESP-01S Relay Adapter Module for Smart Home Appliance Connect Fan Illuminator Smart Switch Phone APP Remote Control Switch Wireless Transceiver: Amazon.com: Industrial & Scientific
ESP8266 Relay Module, Relay Module WiFi 8‑Channel ESP8266 Development Board Wireless Development Board with 1 X Relay Module for Smart Home Wireless Control : Electronics - Amazon.com
Alexa Home Automation System Using NodeMCU & Relay Module - Hackster.io