Macurco CM-2B carbon monoxide gas detector and transducer features a digital display (0-250ppm), NEMA 1 enclosure, 24 VAC or VDC operation, and 4-20ma output. For use with the MACURCO DVP-120 control panel and HVAC/Building Automation Systems. ETL Listed. ***** DISCONTINUED. Replaced by CM-6 *****