Shelly Gas is a Wi-Fi gas detector sold in natural gas (CNG) and LPG versions that raises an alarm the moment a leak is detected, with a built-in siren and self-test.
Sold as separate CNG (natural gas / methane) and LPG variants, each sounding a local 70 dB alarm with a self-test cycle. Pairs with a Shelly valve actuator to shut off the supply on a leak. Mains powered. The native Shelly integration gives local control with no cloud required, plus MQTT support.