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Kidde

Kidde Smoke & Carbon Monoxide Detector with Voice Alerts, Battery Powered, Combination Smoke & CO Alarm, (Pack of 4)

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Availability: Only 9 left in stock, order soon!
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Arrives May 16 – May 19
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Size: 4 Pack


Style: Previous Model


Pattern Name: Detector


Features

  • 2 units in 1: unit alerts you to smoke & carbon monoxide by sounding a loud, 85-decibel alarm & sounding voice alerts
  • Ionization sensor technology senses invisible fire particles, while a electrochemical sensor detects CO gas
  • Voice Alarm & an 85-decibel alarm announces a hazard when detected: Fire! = smoke or fire or Warning Carbon Monoxide = CO gas, or "Replace Battery" when the battery needs to be replaced
  • Operates on 2-AA alkaline batteries, providing reliable detection during a power failure
  • Front-load battery door makes installation & replacement easy
  • Tamper-resistant design: deters removal of the carbon monoxide smoke detector combo from the ceiling
  • Test-Hush Button makes testing the detector or silencing false alarms easy (false alarms may occur from routine cooking, shower steam, dust or humidity)
  • UL listed with a 10-Year limited manufacturer warranty on the alarm only (not a battery performance claim). Warranty begins when the alarm is powered on. If that date is unknown, it should be assumed that replacement is needed.

Description

The Kidde Smoke & Carbon Monoxide Detector with Voice Alerts, Battery Powered, Combination Smoke & CO Alarm, model KN-COSM-BA, provides two fire safety detectors in one unit through the use of ionization sensing technology that senses invisible fire particles, while an electrochemical sensor detects carbon monoxide. When a smoke, fire, or carbon monoxide event occurs, the Kidde fire alarm warns with an 85-decibel alarm sound, flashing LEDs, and voice alerts. For smoke detection, the alarm will sound with the announcement, "Fire! Fire!" and a red LED will flash in unison with the voice alarm. For carbon monoxide detection, the alarm will sound with the announcement "Warning! Carbon Monoxide!". In the event of a low battery, the detector will announce, "Low Battery!" The Kidde combination smoke and carbon monoxide alarm is powered by 2-AA batteries, which provide coverage during a power failure. A convenient pop-up, front-door battery compartment allows for quick installation or replacement of a battery without having to disconnect the entire unit from the ceiling. In the case of nuisance or false alarm, the Smart Hush button silences the unit for approximately 8 minutes, which is helpful when this smoke detector carbon monoxide detector combo sounds from things like routine cooking or shower steam. When installed, the green LED on the alarm will flash every 60 seconds in standby condition, letting you know that the unit has power & is operating correctly. Install a carbon monoxide smoke detector combo on every level of your home and near bedrooms to help keep your family safe. UL Certified with a 10-year limited manufacturers' warranty. Meets requirements of UL 2034, UL217, NFPA72, (chapter 11 2002 edition) The State of California Fire Marshal, NFPA101 (One and two family dwellings) Federal Housing Authority (FHA), Housing and Urban Development (HUD).

Brand: Kidde


Style: Previous Model


Power Source: Battery Powered


Color: White


Item Weight: 0.82 Pounds


Alarm: fire safety, ionization, battery powered, interconnected, tamper-resistant


Operating Humidity: 10% to 95% relative humidity, non-condensing


Upper Temperature Rating: 100 Degrees Fahrenheit


Sensor Type: Ionization


Material: Plastic


Brand: ‎Kidde


Style: ‎Previous Model


Power Source: ‎Battery Powered


Color: ‎White


Item Weight: ‎0.82 Pounds


Alarm: ‎fire safety, ionization, battery powered, interconnected, tamper-resistant


Operating Humidity: ‎10% to 95% relative humidity, non-condensing


Upper Temperature Rating: ‎100 Degrees Fahrenheit


Sensor Type: ‎Ionization


Material: ‎Plastic


Number of Items: ‎4


Manufacturer: ‎Kidde


UPC: ‎047871297979


Part Number: ‎21029797


Item Weight: ‎13.1 ounces


Product Dimensions: ‎2.64 x 1.8 x 5.6 inches


Item model number: ‎KN-COSM-BA


Batteries: ‎2 AA batteries required. (included)


Size: ‎4 Pack


Finish: ‎Uncoated


Pattern: ‎Detector


Shape: ‎Circular


Voltage: ‎3 Volts (DC)


Installation Method: ‎ceiling, wall


Item Package Quantity: ‎4


Mounting Type: ‎brackets


Usage: ‎Inside; Professional


Included Components: ‎battery, brackets


Batteries Included?: ‎Yes


Batteries Required?: ‎Yes


Battery Cell Type: ‎Alkaline


Warranty Description: ‎10 year limited manufacturer


Date First Available: June 30, 2021


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: May 16 – May 19

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews

    • Detect This!
Size: 1 Pack Style: Previous Model Pattern Name: Detector
I purchased this item to replace a smoke/carbon monoxide detector that had expired & no longer would accept a battery replacement. I never realized these detectors "expired" & must be replaced after so many years.
Reviewed in the United States on February 3, 2025 by A Guy in Texas
    • Notes on replacing old model KIDDE units and a fix for locking battery fingers
Size: 1 Pack Style: Previous Model Pattern Name: Detector
I purchased two of these units to replace Kidde's previous generation KN-COSM-B combo smoke/CO2 alarm that reached their "end of life" (EOL). Kidde was very accurate with their EOL beeps. Both of the old KN-COSM-B units were installed at the same time, and both started their EOL beeps within days of each other. I first thought that all I needed was a battery replacement. After trying a number of different types of new batteries to squelch the beeping, I finally decided to read the instructions and realized that the units needed to be replaced. The replacement date I had written on the old units was 10/2016 and since this was now the second week of November when the EOL beeping started, I would say that was pretty accurate. Good Job on that Kidde!! Even though the old and new units are substantially different (number of batteries; location of the batteries; diameter of the unit) I was hoping that the wall bracket was compatible so I wouldn't have to replace it potentially leaving holes that needed to be spackled and painted. I had compared the brackets based upon pictures in the instructions and they looked the same -- so hopefully they would be compatible. The good news is that the new units fit in the old brackets. The not so good news is that the color of the old units brackets is a noticeably few shades lighter. If you are lazy like me, you can just use the old brackets. Alternatively, it would be a simple matter to unscrew the old bracket and screw in the matching new one as the hole positions are exactly the same. I also noticed that a number of reviewers commented on engaging the locking "battery fingers" in the battery compartment and they decided to return the unit. I did the same stupid thing, as I started examining the unit before reading the instructions. What happens is when you open the battery compartment, there is a moisture absorbing silica packet inside. Removing that packet, two reddish "battery fingers" pop up. At this point, you must insert batteries correctly or there could be problems. I started closing the battery door without the batteries, and the fingers engaged preventing the door from either opening or closing. However, there is a fix that I worked out so that you don't have to return the unit. If you unwind a paperclip and bend the end into a small "L", you can use this handmade pry tool to carefully go under the battery lid and disengage the locking fingers. I was able to do this without breaking the fingers or the door, and when I finally inserted batteries into the unit, it tested OK. ... show more
Reviewed in the United States on November 12, 2016 by Jackalope
    • Very Nice Solution for Our Needs -
Size: 1 Pack Style: Previous Model Pattern Name: Detector
In spite of the negative reviews, I decided to get this. And I am very glad I did! It's perfect for our application: we only live in a 700 sq ft place and only had need for one. The Pros: - Stand-alone operation - CO and Smoke Detection - Powered by only (2) AA batteries (much cheaper than 9V and I have lots of rechargeable batteries) - Hush Mode - IT WORKS... almost too well... (in spite of what some of the negative reviews say). - It's inexpensive! There is no down side I've seen (save the hush mode cancels itself when there's no smoke, rather than wait for the 9 minute timer to expire). The hush mode cancellation is hardly a big problem. It's just annoying when we roast coffee because we generate smoke about every 4 minutes for 15-20 minutes. Rather than 1-2 pushes on "hush" (if it was strictly timer-based) you have to push it every time you roast. Or just pull the batteries, then put them back in when you're done. It is VERY sensitive. We don't generate much smoke when we roast coffee, but even though the detector is quite a ways from the source with very good ventilation it still goes off every time. Someone who reviewed this very negatively complained it wouldn't go off with a lighter under it. That's because it's a SMOKE detector. That same genius complained that it wouldn't detect CO with a "scooter" running in a closed garage. Modern vehicles (even small engines) generate far less CO than they did decades ago. Modern vehicles with catalytic converters will generate almost zero CO. One would need to get a lot more creative to test the CO alarm at home. I will not suggest how. I haven't tried. But I'm comfortable with Kiddie's reputation and if the smoke detection is any indication, the CO detection is probably performs as they say it does. Another reviewed blasted it because the "voice" was so quiet. For a combo detector under $30 who cares? Are you going to stand under a blasting alarm (it's VERY loud) straining to hear the voice say "fire" or "carbon monoxide"? Or are you just going to get out of the house? The alarm is going off for crying out loud! A fire should be readily apparent. If it's CO you don't want to be in the house anyway. I hope this style is still around in 10 years when I need to replace this one! ... show more
Reviewed in the United States on September 1, 2016 by Hoopy Frood
    • Replace the batteries provided by the vendor before installing
The smoke detectors do exactly what is required the batteries supplied by the vendor are junk on all 6 smoke detectors the batteries went bad within 2 months of installation even though the use by date was 2026.
Reviewed in the United States on October 12, 2024 by Sandman

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