Google Nest Protect 2nd Generation (Battery) Smart Smoke/Carbon Monoxide Alarm White S3000BWES - Best Buy
Siterlink 2.4G Smart Smoke Detector Carbon Monoxide Detector Combo with Digital Display, 2 in 1 WiFi Fire and CO Alarm Detector, Replaceable Battery, Real-Time Notification, UL217 UL2034, 1 Pack - Amazon.com
Smoke + Carbon Monoxide Alarm with smart features | Kidde
SITERWELL 2.4G Smart Smoke Detector Carbon Monoxide Detector Combo with LCD Display, 2 in 1 WiFi Fire and CO Alarm Detector, Replaceable Battery, Conforms to UL 217 & UL 2034 Standards, 1 Pack - Amazon.com