The 5800CO is a 3V battery powered wireless carbon monoxide (CO) detector intended for use with Honeywell Home alarm systems that support 5800 Series wireless devices. It provides early warning when its electrochemical sensing technology measures carbon monoxide levels in the air. The 5800CO is specifically designed for system operation and is fully listed to UL 2075 as a system supervised detector.* It contains a piezoelectric horn which generates the ANSI S3.41 temporal 4 pattern in an alarm condition.The 5800CO is a 3V battery powered wireless carbon monoxide (CO) detector intended for use with Honeywell Home alarm systems that support 5800 Series wireless devices. It provides early warning when its electrochemical sensing technology measures carbon monoxide levels in the air. The 5800CO is specifically designed for system operation and is fully listed to UL 2075 as a system supervised detector.* It contains a piezoelectric horn which generates the ANSI S3.41 temporal 4 pattern in an alarm condition.