 - 120-volt hardwire ionization smoke alarm
- Uses Smart Technology to reduce nuisance alarms
- Features convenient silence/test button, dust cover, 85-decibel alarm
- Latching alarm indicator identifies which unit triggered alarm
- 9-volt battery included; 10-year limited warranty
List Price: $17.99
Lowest Price: $8.99 
Amazon.com Product Description: Introducing the revolutionary BRK 9120 series smoke alarms which have been redesigned from the ground up. They install faster, perform better, and are even smarter than before. All of these improvements help reduce nuisance alarms and save you time and money. BRK Electronics smoke alarms are designed to be easy to install, easy to maintain, and quality-engineered for years of virtually maintenance-free service. The 9120B AC-powered smoke alarm with battery backup includes these features: - Ionization sensor which helps detect fast flaming fires that consume combustible materials rapidly.
- 120-volt AC inter-connectable (with maximum 18 compatible devices). The alarm can be interconnected with up to 12 other compatible smoke alarms and six compatible devices like bells, horns, repeaters and door closers. If one unit triggers an alarm, all smoke alarms in the series will sound. Power indicators show which unit in the series initiated the alarm.
- Latching alarm indicator which automatically identifies which unit initiated the alarm.
- Smart technology to reduce nuisance alarms.
- 9-volt battery backup for peace of mind during power malfunction.
- Single test/silence button which both silences a non-threatening alarm or low battery warning and allows you to test the unit's functionality.
- Perfect mount system including a gasketless base for easy installation and new mounting bracket that keeps the alarm secure over a wide rotation range to allow for perfect alignment.
- Mounting bracket lock for tamper resistance.
- Dust cover to keep unit clean during construction.
- 10-year limited warranty.
All BRK Electronics smoke alarms meet UL 217 standard and are listed with the California State Fire Marshal. They use the new UL mandated repeating 85-decibel alarm horn pattern. 10-year limited warranty. This unit is approved for sale in Oregon after new revisions on law HB2586.--Bree NorlanderWhat's in the Box
One smoke alarm, one 9-volt battery, and user's manual
Customer Reviews: Rating: 
Date: 2008-06-18
Junk
My house is a two year "upscale" with these placed in varying areas throughout. Just about all have had the "false alarm" chirping. I have replaced the batteries to no avail. Don't waste your money on them! Rating: 
Date: 2008-05-20
Remember to follow maintenance directions.
The instructions say to vacuum with a soft brush attachment and to test once a month. As with many electronics, dust is a big issue. As well as storms and power surges. We have these units throughout our home and the have worked reliable until we started have random beeping in different rooms. We read the instructions, starting cleaning the units and testing them. All but one stopped beeping. I went on line to read the trouble shooting directions and did everything. The unit still beeped once the next day. I called customer service. They talked me through what I had done, said that it is under warranty and are send me a new unit. Absolutely no hassles. Rating: 
Date: 2008-05-17
replacing old hardwire alarm
I just purchased 3 of these to replace 15 year old BRK hardwire units that were in my house. The alarms on the old units were starting to go off randomly at all hours. I decided, despite reading other reviews on this product, to purchase the same brand since they weren't very expensive and they had several good features. I took the old ones out and replaced the new ones in under 10 minutes. It was quite easy. Although I've only had them a few days, no random alarms are going off. Rating:
Date: 2008-04-07
Good thing I checked the reveiws on 4120B replacement.
I too have had to endure sleepless nights because of the 4120b It's now obvious this company manufactures junk and has probably ended more lives due to suicide than they've saved from fires. Our home was outfitted with 4 and within a few months they started chirping. Their website is useless. They've since been removed and used for target practice.
Now to find a brand to replace them. Rating:
Date: 2008-03-13
Meaningless Chirps
These alarms in my house also suffer from meaningless chirps, which tend to occur at the wee hours of the am. Quite an annoyance. | 
