High performance electrochemical sensor (with 10-year life) to detect the presence of CO. The sensor is individually calibrated and tested in CO gas to ensure accuracy. In alarm, the flash rate of the red LED indicates the level of CO detected. Alarm triggers at 50ppm within 60-90mins, 100ppm within 10-40mins and 300ppm within 3mins. Interlinked via Wireless or when Hardwired (Wireless Module Required) 230V AC Mains-Powered with Battery Backup 10-Year Sealed Tamperproof Lithium Integrated Battery 85dBA Alarm at 3m Test/Hush Button Built-In AudioLINK Data-Extraction Technology Easi-Fit Base Interlinked via Wireless or when Hardwired (Wireless Module Required) 230V AC Mains-Powered with Battery Backup 10-Year Sealed Tamperproof Lithium Integrated Battery 85dBA Alarm at 3m Test/Hush Button Built-In AudioLINK Data-Extraction Technology Easi-Fit Base