The NO2 transmitter monitors nitrogen dioxide (NO2) and is designed for the continuous monitoring of vehicle exhaust in non-hazardous areas. A wide spectrum, long life electrochemical sensor measures the amount of CO  or NO2 in the environment. Both the Room and Duct transmitters are offered in a standard NEMA 1 rated  plastic enclosure. An optional NEMA 4X watertight and dust proof enclosure is available with the room transmitter. Other options include an LCD display with (2) SPDT Form 1C relays and a buzzer. The NO2 Series is covered by ACI's Two (2) Year Limited Warranty.