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Model # 21007588

Internet # 202029423

Store SKU # 802605

120-Volt Hardwired Inter Connectable Smoke Alarm with Battery Backup (4-Pack)

This item has been discontinued.
The Home Depot no longer carries this specific product.

$54.00 /each




Model # 21007588

Internet # 202029423

Store SKU # 802605

The Walter Kidde Hardwire Smoke Alarms (4-Pack) alert you to potential fire dangers by detecting the presence of smoke and heat in the atmosphere. These alarms are equipped with 2 pre-stripped wires for easy installation and have a 9-Volt battery backup to ensure continued use during a power failure. The alarms feature a dust cover that protects the internal sensor from airborne contaminates that may take flight during a fire or a construction job.

  • Detects smoke and heat for reliable protection against fire
  • Hush alarm control button silences false alarms
  • Test button allows you to check functionality without sounding the full alarm
  • 9-Volt battery backup provides protection during power outages
  • Battery is easily accessible through the front pull tab
  • Pre-stripped wiring harness with easy-off cap ensures quick installation
  • Dust cover protects the sensor from contaminates
  • 4 detectors included (part # i4618)
  • 360 degree mounting bracket allows mounting from any angle

Info & Guides

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Product Depth (in.) 
Product Height (in.) 
Product Width (in.) 
Alarm Sensor Type 
Alarm Type 
Alarm/Detector Features 
Battery Back-Up,Hush Feature,Interconnected,Value Pack 
Commercial / Residential 
Commercial / Residential 
Connector/Contact Type 
Power Source 
Voltage (volts) 
Warranty / Certifications
Certifications and Listings 
1-UL Listed 


Rated 4.3 out of 5 by 62 reviewers.
Rated 5.0 out of 5.0 by Easy replacement Not sure how to review these but HD asked me to so I will. Had a different brand throughout the house. Went to change batteries on one and the terminals were corroded so bad I couldn't pull it free of the battery and broke the wires. So, I decided to buy new instead of trying to clean and repair the existing (safety matters) Also, after reading that smoke alarms should be replaced every ten years, I decided to swap out all of them in the house. (After fifteen years, some of the originals had yellowed so bad they were unsightly. So, it was off to Home Depot. I needed eight of these so I bought the four packs for a slight savings over the singles. They are very easy to swap out. two screws hold the mounting plate to the outlet box. Wire it to the existing wires, snap in place and pull the paper tab out to engage the included battery (Yes! it includes a battery) Changed out all six in about 45 minutes. All I needed was a step ladder, a phillips screw driver and a pair of wire strippers. All in all, with the included batteries and the ease of installation, these were a good value. Finally, I do like the front battery door feature and the fact that the battery simply pushes in place instead of the usual nine volt wired terminal. It will certainly make changing batteries on all eight of them much less a chore. June 30, 2015
Rated 5.0 out of 5.0 by Good value, no unnecessary bells and whistles. So far so good Used two of these reasonably priced 4-packs to replace eight older Kidde alarms, since two of them had failed after about 7 years. Have 8 interconnect alarms in my home, so a false alarm in the middle of the night is not pleasant. Was able to use the existing AC quick connect wiring (Kidde/Firex standard) which cut down on replacement time. I like the new accessible battery compartment that doesn't require unmounting the alarm. After installation, all tested well interconnected, with hopefully no false alarms to come. The dust cover mentioned in the description is simply a "mini shower cap" the protects the alarm while building construction is in progress. You don't want to leave it on. March 20, 2012
Rated 5.0 out of 5.0 by Easy install Very easy install great price too. Replaced existing hard wired detectors with these October 27, 2015
Rated 4.0 out of 5.0 by Easy to install These devices were easy to install. I replaced my old ones that were over 10 years old because one would go off randomly and set them all off. Since it is a life safety device it wasn't worth guessing just replaced all of the old ones with new. The installation is easy color to color splice, run in two screws, and snap it together. The test feature works, but can speak for how they work in an actual fire since I haven't had a fire. I'm not sure of the life expectancy, but given the age of the old one and it is a small price for piece of mind with a family. March 10, 2015
Rated 4.0 out of 5.0 by Easy install We bought these to replace the 10+ years ones we had. The connection was different then the original but it was still the same brand. Easy to change out the connectors and put them right in. Total time took only about 30 minutes for 5 change outs. September 1, 2015
Rated 5.0 out of 5.0 by God buy and easy install Purchased to replace existing alarms that were false alarming. Easy to insall and a good value with no more false alarms. July 28, 2015
Rated 4.0 out of 5.0 by great design Simple mounting hardware and electrical hook up with great look April 14, 2015
Rated 5.0 out of 5.0 by Easy Replacement I replaced three 25+ year old smoke alarms using this product. They were relatively easy to install and wire up. The battery backup is an added feature I didn't previously have. I haven't yet had a nuisance alarm go off near the kitchen area where smoke from normal cooking occurs. I had disconnected the old smoke detector in that area many years ago for that reason. March 16, 2015
  • 2015-11-22 T10:21:07.938-06:00
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