First Alert Hardwired Talking Photoelectric Smoke and Carbon Monoxide (CO) Detector, 2-Pack | Costco
BRK First Alert CO5120BN Hard-Wired Carbon Monoxide Alarm with Backup
First Alert BRK CO511 Carbon Monoxide (CO) Detector Wireless Interconnected with Voice and Location - Combination Smoke Carbon Monoxide Detectors - Amazon.com
First Alert 10-Year Battery-Operated Combination Smoke and Carbon Monoxide Detector in the Combination Smoke & Carbon Monoxide Detectors department at Lowes.com