X-Sense 2-in-1 Smoke and Carbon Monoxide Detector Alarm (Not Hardwired), 10-Year Battery-Operated Dual Sensor Fire & CO Alarm, Compliant with UL 217 & UL 2034 Standards, SC06 - Amazon.com
Kidde FYCO3IN Hard Wired CO Detector with Battery Backup
BRK Electronics CO5120BN Hard Wired T4 Carbon Monoxide Alarm with Backup - Vaughn Engineering