The macurco 12-series are line Voltage powered (100-240vac), dual relay gas detector, Controller and transducers. The 12-series utilizes an internal switching power supply that is capable of using line Voltage between 100 and 240VAC and 50-60HZ. The 12-series have selectable 4-20ma output, Buzzer and Digital display options. It is an electronic detection system used to measure the concentration of various gases and provide feedback and automatic control to help reduce gas concentrations in parking garages, maintenance facilities or other commercial applications.