⚠️ The following (3) for gas natural gas gas gas liquefied gas and other gas leakage alarm ⚠️ (210 alarm) APP monitoring + voice mobile phone alarm + concentration temperature display + send 2 meters power cord (218 gas alarm) APP monitoring + voice mobile phone alarm + power supply (send 2 meter line) ⚠️ The following alarm for charcoal coal gas liquefied gas and other carbon monoxide alarm (002 carbon monoxide alarm ⚠️) sound and light alarm + concentration display + low power consumption with 9V carbon battery