firex smoke alarm 120 538b replacement

First Alert 2pk 10-Year Battery Photoelectric Smoke Alarm with Slim Profile

First Alert Alarm Smoke AC/DC with ADP SMI100-AC: Hardwired Smoke Detector, Fire Alarm, Lithium Battery, 10-Year Warranty

First Alert Alarm Combo DC10 with VCE SMCO210V Clam Tray: Smoke & Carbon Monoxide Detector, Fire Alarm, 10-Year Warranty

First Alert SMI100-AC, Hardwire Interconnect Smoke Alarm with Battery Backup, 3-Pack

First Alert 9120B-AC BRK, Hardwire Interconnect Smoke Alarm with Battery Backup

First Alert® SMI100 Battery-Operated Smoke Alarm

First Alert BRK SC-9120B Hardwired Smoke and Carbon Monoxide (CO) Detector with Battery Backup

First Alert SMI100-AC, Hardwire Interconnect Smoke Alarm with Battery Backup

First Alert 9120B Smoke Detector, Hardwired Alarm with Battery Backup, 3-Pack

First Alert SMICO100-AC Interconnect Hardwire Combination Smoke & Carbon Monoxide Alarm with Battery Backup

First Alert SM100V-AC, Interconnect Hardwire Smoke Alarm with Battery Backup & Voice Alerts, 1-Pack

First Alert Smoke Alarm, Interconnect Hardwire Detector with Battery Backup, SMI100-AC, 3-Pack

First Alert Alarm Combo DC RFID SMCO500V Clam Tray: Smoke & Carbon Monoxide Detector, Battery Included, 10-Year Warranty

First Alert Alarm Combo DC10 with VCE SMCO210V Clam Tray: Smoke & Carbon Monoxide Detector, Fire Alarm, 10-Year Warranty

First Alert Alarm Smoke DC10 SM210 Clam Tray: 10-Year Lithium Ion Battery, Fire Alarm, No Hardwired Installation Required

First Alert Precision Detection Interconnect Hardwired Smoke Alarm with 10-Year Battery Backup

First Alert Alarm Combo DC Slim SMCO210 Clam Tray: Smoke & Carbon Monoxide Detector, Fire Alarm, Lithium Battery, White

First Alert Alarm Smoke AC/DC with ADP SMI100-AC: Hardwired Smoke Detector, Fire Alarm, Lithium Battery, 10-Year Warranty

First Alert 8E Photo Micro Smoke Detector 10 Year Battery

First Alert® SMI100 Battery-Operated Smoke Alarm

First Alert 9120B-AC BRK, Hardwire Interconnect Smoke Alarm with Battery Backup

First Alert BRK SC-9120B Hardwired Smoke and Carbon Monoxide (CO) Detector with Battery Backup

First Alert SMI100-AC, Hardwire Interconnect Smoke Alarm with Battery Backup

First Alert 9120B Smoke Detector, Hardwired Alarm with Battery Backup, 3-Pack

First Alert SMI100-AC, Hardwire Interconnect Smoke Alarm with Battery Backup, 3-Pack

First Alert SMICO100-AC Interconnect Hardwire Combination Smoke & Carbon Monoxide Alarm with Battery Backup

Water Leak Monitoring Sensor with Alarm 6 Pack - Leak Puppy Electronic Water & Flood Leak Detector - Detects as Little as 1/32" of Water - Overflow

First Alert SM100V-AC, Interconnect Hardwire Smoke Alarm with Battery Backup & Voice Alerts, 1-Pack

First Alert Smoke Alarm, Interconnect Hardwire Detector with Battery Backup, SMI100-AC, 3-Pack

Leak Puppy Electronic Water Alarm- Detects as Little as 1/32" of Water- Leak Detector Beeps When Battery is Low