Goouuu-S1 ESP8266
This is an ESP8266 based board, in case you buy one of these here is some info I have found
Goouuu-S1 ESP8266 WiFi module is...
Wemos and MQ-4 gas sensor
The MQ-4 Methane Gas Sensor is a gas sensor that detects the presence of methane gas at concentrations from 200 ppm to 10,000 ppm, a range...