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Kidde Fire Sentry Micro Profile 3 Year Smoke Alarm, 9 Volt Battery
Key item features
- Compact Design: At only 4-inches in diameter, this smoke alarm is suitable for installation in tight spaces within homes, RVs, and mobile homes.
- Ionization Detection: Utilizes ionization sensor technology to detect invisible fire particles associated with flaming fires sooner than photoelectric alarms.
- Battery Powered: Operates on a 9-volt alkaline battery, providing reliable detection of smoke or fire even during power outages and allowing for easy, wire-free installation.
- Audible Alert: When smoke or fire is detected, an 85-decibel alarm will sound, accompanied by a red LED indicator.
- Convenient Features: Includes a test-hush button for battery operation checks and silencing nuisance alarms from cooking or shower steam, with a chirp indicating low battery.
- Safety Standards: Meets the requirements of UL 217, NFPA72 (chapter 11 2002 edition), NFPA101 (One and two-family dwellings), and Federal Housing Authority (FHA).
Generated by AI
Specs
- Battery life3 years
- Decibel rating85 dB
- FeaturesLow Battery Indicator
- Power typeBattery
- Smoke & carbon monoxide alarm sensor technologyIonization Sensor
- Smart techY
Reviews summary
Pros
- : Offers a low-cost option.
- : Compact design and simple mounting system make it quick.
- : Has a small, low profile.
- : Offers protection without breaking the bank.
Neutral
- : Can be easy to hang, but hole may be too small.
Generated by AI
Current price is USD$9.99
Price when purchased online
Not Available
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About this item
Product details
The Kidde Fire Sentry Smoke Detector, 9V Battery Powered Smoke Alarm, 4 Inch Compact Design, model i9040, is a smaller designed, 4-inch diameter smoke detector that you can install in tight spaces in your home, your RV, or mobile home. The Kidde Smoke Detector uses ionization sensor technology to detect invisible fire particles (associated with flaming fires) sooner than photoelectric alarms. When smoke or fire is detected, an 85-decibel alarm will sound. The Kidde Smoke Detector is powered by a 9-volt battery, which provides easy installation since the alarm requires no wiring, plus coverage during a power failure. A red LED indicates that the smoke detector is sensing smoke or fire. A test-hush button allows you to test the battery operations as well as silence nuisance alarms that may occur from cooking or shower steam. The Kidde Smoke Detector will chirp when it's time to replace the battery. Install a smoke detector & carbon monoxide detector on every level of your home and near bedrooms to help keep your family safe from fire & poisonous gas. UL Certified with a 3-year limited manufacturer's warranty (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. Meets requirements of UL 217, NFPA72 (chapter 11 2002 edition), NFPA101 (One and two-family dwellings), and Federal Housing Authority (FHA).
- At only 4-inches in diameter, this is one of the smallest smoke detectors you can install in your home, RV, and mobile home
- Basic ionization smoke alarm, affordable and simple to use to provide detection of dangerous smoke or fire
- Operating on a 9-volt alkaline battery, the Kidde smoke alarm provides reliable detection of smoke or fire, even during power outages
info:
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Specifications
Battery life
3 years
Decibel rating
85 dB
Features
Low Battery Indicator
Power type
Battery
Warranty
Warranty information
3 year limited warranty
Warranty url
Warnings
Ingestion Hazard
This product contains a battery. Death or serious injury can occur if ingested. A swallowed battery can cause Internal Chemical Burn in as little as 2 hours. Keep new and used batteries OUT OF REACH OF CHILDREN. Seek Immediate medical attention if a battery is suspected to be swallowed or inserted inside any part of the body.
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Customer ratings & reviews
How item rating is calculated
Reviews summary
Pros
- : Offers a low-cost option.
- : Compact design and simple mounting system make it quick.
- : Has a small, low profile.
- : Offers protection without breaking the bank.
Neutral
- : Can be easy to hang, but hole may be too small.
Generated by AI
Customer images
+7 images
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Showing 1-3 of 593 reviews
Nov 26, 2025
Fidgety
Item details
Count per pack: 1
5 out of 5 stars review
Verified Purchase
Simple old school detector at a great price.
Simple old school detector at a great price. I got two more for other areas of the house. There's no fiddling with apps or settings, no wifi required. A couple screws to install the mounting bracket, add the included battery and twist into place = DONE.
Helpful?20AP8RHJACU925488877
reply from Kidde Expert
Thank you for sharing your feedback! We love seeing that our products work great for you!
Jan 29, 2026
ray
Item details
Count per pack: 2
5 out of 5 stars review
Verified Purchase
New smoke detector
It was easy to install and now I can rest in peace and confidence knowing I replaced my old one, it was chirping letting me know it was time to replace.
Helpful?20AP8RHJACU925488877
reply from Kidde Expert
Thank you for your glowing review! We’re thrilled to hear you enjoyed our Kidde Fire Sentry Battery Operated 4-inch Smoke Detector, and we will continue our efforts to provide innovative solutions to help create a safer world.
Feb 3, 2023
ejlow
5 out of 5 stars review
Verified Purchase
Small but mighty
Small but mighty. Came with a battery. Put one on each floor, stairway and in each bedroom. It blinks a red light, but not often and it’s subtle. Doesn’t grab your attention when you’re in bed, thank goodness. 8 minute pause button for when you accidentally burn your pizza but don’t want to tame the entire thing down and remove battery to make it shut up then forget to put it back. So highlyyy recommend this smoke detector.
Helpful?20AP8RHJACU925488877
