| First Alert Smoke & Carbon Monoxide Alarm in Black/Gray | 5.6 H x 5.6 W x 1.75 D in | Wayfair SC9120B First Alert BRK SC9120B Hardwired Smoke Detector and Carbon Monoxide (CO) Detector with Battery BackupFeatures:Keep your family safe with this hardwired smoke and carbon monoxide alarm; the battery backup means constant monitoring, even if there's a... more | | $49.50 FREE shipping go to store |