First Alert BRK SC-9120B Hardwired Smoke & CO Detector with Battery Backup

Reliable 24/7 protection for your home

The First Alert BRK SC-9120B is a hardwired smoke and carbon monoxide detector designed to run on 120V with a reliable battery backup. It combines robust sensing with practical features to fit a variety of homes, from apartments to family living spaces.

Smart sensing you can rely on

This unit pairs an electrochemical CO sensor with a dual ionization smoke sensor. The combo is designed to detect common smoke and CO patterns quickly, helping you notice danger sooner while reducing unnecessary nuisance alerts.

• Inter connects with BRK and First Alert hardwired alarms for expanded coverage
• Easy universal mounting bracket simplifies installation
• Clear silence and test controls with separate smoke and CO indicators
• 9 volt battery included and a long term warranty supports ongoing protection
• Faster job site turnarounds thanks to straightforward wiring and mounting

Easy to install and maintain

Designed with a large mounting bracket opening and keyhole slots, the unit is easier to align and mount on ceilings or walls. A side access battery compartment lets you replace the battery without removing the detector. When connected to AC power via the quick connect harness, protection remains steady.

• Battery backup keeps protection during power outages
• Low battery chirp can be silenced for up to eight hours when needed
• End of life signaling provides a clear alert when replacement is due

Security, reliability, and peace of mind

Two built in locking features deter theft in shared spaces. The unit remembers which detector silenced an alarm, aiding quick interpretation during the event. A seven year limited warranty adds long term value to your safety setup.

Ideal for bedrooms, living rooms, hallways, and basements, this detector fits a range of ceiling heights and layouts. The audible alerts are designed to be clear and distinct for smoke versus CO, helping occupants decide how to respond. Warranty and origin details reflect a focus on durable, dependable home safety equipment. This device is designed for straightforward maintenance and dependable performance across many home configurations.