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Main product image of i12040 Hard-Wired Interconnect Ionization Smoke Alarm, Rear Load (120v) w/ Front Pull Tab and 9v Battery Backup
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i12040 Hard-Wired Interconnect Ionization Smoke Alarm, Rear Load (120v) w/ Front Pull Tab and 9v Battery Backup

Brand:
Kidde
SKU:
21006378
Rating:
(8)
Q&A:
(0)
i12040 Hard-Wired Interconnect Ionization Smoke Alarm, Rear Load (120v) w/ Front Pull Tab and 9v Battery Backup
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21006378 has been discontinued
Discontinued February 23, 2026
This product was discontinued by the manufacturer.
Suggested Alternative:
SMACFEX Hard-Wired Firex Smoke Alarm (120 V) with AA Backup Battery
Brand:
Kidde
SKU:21033081
(3)
Order by 6PM, receive 176 by Tomorrow
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Product Highlights

Product Highlight: Temperature Range (F)
40°F to 100°F
Product Highlight: Diameter (Inches)
5.6" Diameter
Product Highlight: Depth (Inches)
1.55" Depth
Product Highlight: Warranty
10 Year Limited Warranty
Product Highlight: Voltage
120v

Description

Product Description


The Kidde i12040A is an AC/DC powered, ionization smoke alarm that operates on a 120V power source with 9V battery backup. This alarm uses ionization sensing technology. Ionization sensing alarms may detect invisible fire particles (associated with flaming fires) sooner than photoelectric alarms. Photoelectric sensing alarms may detect visible particles (associated with smoldering fires) sooner than ionization alarms. Kidde strongly recommends that both ionization and photoelectric smoke alarms be installed to help insure maximum detection of the various types of fire that can occur within the home.


This smoke alarm is available in a 6-piece cut case with tray for easy display as well as a 6-piece bulk pack for contractors and property owners. This unit is a UL Listed product with a 10-year limited warranty.


Features:

  • Front battery pull tab allows battery activation without removing alarm from mounting bracket.
  • Large mounting base makes mounting easier, protects surface paint from dirt and covers imperfections.
  • Pre-stripped wiring harness with easy off cap does not require stripper tool. Tinned strands increase conductivity and wire nut grip.
  • One button design for easy operation and less confusion. Operates Hush and alarm test.
  • Battery run down protection will shut down alarm memory when AC power is not present, reducing low battery chirp.
  • Dust cover protects sensor from contaminates during construction reducing nuisance alarms.
  • Tamper resist locking feature deters alarm theft.
  • Alarm memory flashes red LED indicating which unit was the initiating alarm in interconnected system.
  • Interconnectable with up to 24 devices (of which 18 can be initiating) including smoke, CO and heat alarms. See user's guide for complete instructions.

Specs

Product Type:

Smoke Detector

Temperature Range (F):

40°F to 100°F

Diameter (Inches):

5.6"

Depth (Inches):

1.55"

Humidity Range:

5 to 95% RH

Warranty:

10 Year Limited

Sensor Type:

Ionization

Voltage:

120v

Battery Type:

9V

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Product Reviews

4.75 out of 8 reviews
88% would recommend this product
4.75
out of 8 Reviews
88% would recommend this product
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5 star
88%
4 star
0%
3 star
13%
2 star
0%
1 star
0%
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Showing 1-8 of 8 reviews

Kiddie Smoke

Nice package , but came with dead battery, not cool
storman
webster springs wv
2 years ago
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Replacements fit nicely

These replacements fit nicely. I was overdue for them.
Chris
Englewood, OH
2 years ago
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yes

I like to Thank You for your outstanding services and customer friendliness that I got was the best. I give you a five star.
Dill
Ga
2 years ago
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I would buy this product again should the need arise.

Installed as a replacement in the master bedroom.
Jack
Smyrna, DE
2 years ago
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i12040 Hard-Wired Interconnect Ionization Smoke Alarm, Rear

Exactly what we needed!
Marty
Oklahoma City, OK
3 years ago
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Quick and Accurate

Great price and quick shipping. Direct replacement.
Dave P
Prattsburgh, NY
6 years ago
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This is a good direct replacement and should be replaced

This model is a good replacement for wired with battery backup model that's connected in series with other detectors. The sensors are not eternal and need to be replaced within 10 years. In my experience, these are good for about 5-7 years.
JD-SD
San Diego
6 years ago
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Exactly as described

Product shipped quickly and was a perfect replacement for my outdated model. Product used the same mount and wiring harness so the replacement was fast and easy. Prices were great! Will use this company again!
Sean
Oklahoma
6 years ago
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