About 238,000 results
Open links in new tab
  1. SC9120B Hardwired Smoke and Carbon Monoxide Alarm with …

    The First Alert Combination Smoke and Carbon Monoxide Alarm detects two threats, smoke and carbon monoxide, in a single device. This 2-in-1 hardwired alarm has lights on the face of the …

  2. Hardwired Combination Smoke and Carbon Monoxide Alarm ... - First Alert

    The First Alert SC9120B Hardwired Combination Smoke and Carbon Monoxide Alarm is a hardwire alarm with battery backup. The hardwired detector includes a 9-volt battery backup …

  3. On a peaked, gabled, or cathedral ceiling, install the first Smoke/CO Alarm within 3 feet (0.9 meters) of the peak of the ceiling, measured horizontally. Additional Smoke/CO Alarms may …

  4. First Alert BRK Hardwired (with Battery Backup) Ionization ...

    Feb 7, 2025 · Using a 9-volt backup battery, the smoke and carbon monoxide detector can function even in the event of a power outage. Additionally, the Co smoke alarm features a …

  5. First Alert BRK SC-9120B Hardwired Smoke and Carbon …

    Jan 1, 2008 · Quick plug-in power connector for easy installation. 120-volt AC inter-connectable with BRK and First Alert hardwired smoke and carbon monoxide alarms. This 2-in-1 …

  6. User manual First Alert SC9120B (English - 11 pages)

    Manual First Alert SC9120B. View the First Alert SC9120B manual for free or ask your question to other First Alert SC9120B owners.

  7. First Alert BRK SC9120B Hardwired Smoke & CO Detector with …

    This First Alert SC9120B Hardwired Smoke and Carbon Monoxide Detector includes a 9-volt battery backup that continues to protect you in the event of a power failure. The alarm features …

  8. First Alert Hardwired Interconnected Smoke and CO Alarm with …

    The SC9120B hardwire alarm comes with 2-in-1 protection to detect CO you can"t see, smell or taste in the air, as well as first signs of a potential fire. This alarm works exceptionally well by …

  9. What Is the Best First Alert SC9120B Replacement?

    Nov 10, 2025 · Find the exact First Alert replacement model that connects directly to your existing SC9120B wiring harness.

  10. Product: SC9120B - First Alert

    Find more information about your First Alert or BRK product, including manuals, tutorials, and more.