AC Powered Ionization Smoke Alarm
with Battery Back-Up and
Silence Feature
Cat. 4120SB

Input: 120V AC, 60Hz, 0.5A

AC Powered Ionization Smoke Alarm
with Battery Back-up
Cat. 4120B

Input: 120V AC, 60Hz, 0.5A
Model
4120B
4120SB M06-2016-007 06/00

User’s Manual

Smoke Alarms

Ionization smoke alarms are generally more effective at detecting flaming fires which consume
combustible materials rapidly and spread quickly. Sources of these fires may include paper burning in a
wastebasket, or a grease fire in the kitchen.
Photoelectric smoke alarms are generally more effective at detecting smoldering fires which smolder for hours
before bursting into flame. Sources of these fires may include cigarettes burning in couches or bedding.

For maximum protection, use both types of smoke alarms on each level of your home.