The GD-2B is a low voltage electronic detector of combustible, heating type gases. The GD-2B is designed for connection to Fire Alarm/Burglary Control Panels. The GD-2B is intended for installation in buildings in non-hazardous locations such as residences, retail stores, office buildings, and institutional buildings. This combustible gas detector has been calibrated for detection of methane (natural gas) and propane (LP) gas. It is NOT designed to detect smoke, fire or carbon monoxide.