(12) Smoke & Carbon Monoxide Alarm AC Powered BRK First Alert Model SC9120B
Alkaline battery Back-up

Maintenance-Free.

Latching alarm indicator

Intelligent Sensing Technology

Smart Interconnect

Two Silence Features

Perfect Mount

Dust Cover

One Alarm protects against two deadly household threats.

Requires only one junction box. Saves installation time

Complies with:

Underwriters Laboratoris (UL)
California State Fire Marshal (CSFM)
Federal Housing Authority (FHA)
Housing and Urban Development (HUD)
National Fire Protection Association (NFPA)

See it here from $39.99 each (opens in new window)

These are new in unopened boxes.