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Internet # 100051755

Model # 21008051

Store SKU # 182262

Store SO SKU #198092

Top Rated

Code One Battery Powered Smoke Detector with Ionization Sensor

Limit 24 per order
$6.97
  • Only 4 inches in diameter - fits in tight spaces
  • Operates on a 9-Volt alkaline battery (included) = no hardwiring
  • Basic ionization smoke alarm, affordable and simple to use
  • View More Details

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Product Details

About This Product

Protect your family with the Kidde Code One Smoke Detector, Battery Powered with Ionization Sensor, Smoke Alarm. The Kidde Code One Smoke Detector, Battery Powered with Ionization Sensor, Smoke Alarm operates on one, 9-volt, alkaline battery. Using ionization sensing technology, the Kidde Code One Smoke Detector, Battery Powered with Ionization Sensor, Smoke Alarm alerts to invisible fire particles, even during power outages and also provides a low battery warning when the battery needs to be replaced. After 10 years of use, the Kidde Code One Smoke Detector, Battery Powered with Ionization Sensor, Smoke Alarm will need to be replaced. UL Certified with a 10-year limited warranty. Meets requirements of UL 217 NFPA 72, The California State Fire Marshall, MFPA 101, and FHA.

Highlights

Product Information

Internet # 100051755

Model # 21008051

Store SKU # 182262

Store SO SKU #198092

Specifications

Dimensions

Product Depth (in.)

4 in

Product Width (in.)

4.0625 in

Details

Alarm Sensor Type

Ionization

Alarm/Detector Features

Hush Button

Alert Type

Siren

Battery Type Required

9-volt

Commercial/Residential

Home

Included

Batteries

Pack Size

1

Power Source

Battery

Returnable

90-Day

Voltage (V)

9

Warranty / Certifications

Certifications and Listings

UL Listed

Questions & Answers

Do it have a cremera on it
ByJun 2, 2026
1 Answer | 
Answer This Question

Hello. No. We do not sell smoke alarms with cameras. We do not sell any products with cameras at this time.

By|Jun 2, 2026


    If we can no longer purchase this due to new safety standards, why not take it off the site?
    ByMar 27, 2026
    1 Answer | 
    Answer This Question

    They are still legal for use as auxiliary or additional smoke alarms in some applications in some parts of the country. It depends on local and state fire codes.

    By|Mar 30, 2026


      Can I no longer purchase this specific model?
      BySep 30, 2025
      1 Answer | 
      Answer This Question

      Hello. No, it does not meet the new standards for smoke alarms. You will want the 10SDR smoke alarm which replaces it.

      By|Sep 30, 2025


        Why is this smoke detector Out of stock, is it a liability of poor performance or manufacturing issue?
        ByApr 4, 2025
        1 Answer | 
        Answer This Question

        Hello. This older alarm meets the 6th edition of the UL 217 standards for smoke alarms. It does not meet the newer 9th edition standards that now include not going off for cooking, the "hamburger test" standard where it literally can't go off for cooking meat underneath it, mostly. Our newest version is the 10SDR smoke alarm.

        By|Apr 4, 2025


          Is ionization or photoelectric better for a smoke alarm
          ByJan 17, 2025
          1 Answer | 
          Answer This Question

          Ionization smoke alarms can sometimes be faster for detecting fast-moving fires, while photoelectric smoke alarms can sometimes be faster for detecting smoldering fires. Ionization alarms can have greater sensitivity to steam, heat, and humidity. Photoelectric alarms can have greater sensitivity to dust, debris, and insects. Either technology should have sufficient reaction time to protect you and go off for any kind of fire at the UL sensitivity as all of our smoke alarms are UL tested and listed.

          By|Apr 4, 2025

            (1)

            Can this replace a code one model AD smoke detector 120 volt 60 HZ and .05 amps
            ByOct 6, 2024
            1 Answer | 
            Answer This Question

            Hello. No, this alarm is not hardwired. There is no direct replacement for your alarms. That being said, you can use any of the Kidde current hardwired smoke alarms to replace your older alarms. You will have to take down all of the older alarms before putting up any new alarms. You will have to change out and rewire the wiring harness plugs at each location. You will have to change out the mounting brackets at each location but that will just take a screwdriver to change out.

            By|Oct 10, 2024


              Can this replace a code one model AD smoke detector 120 volt 60 HZ and .05 amps
              ByOct 6, 2024
              1 Answer | 
              Answer This Question

              Hello. No, this alarm is not hardwired. There is no direct replacement for your alarms. That being said, you can use any of the Kidde current hardwired smoke alarms to replace your older alarms. You will have to take down all of the older alarms before putting up any new alarms. You will have to change out and rewire the wiring harness plugs at each location. You will have to change out the mounting brackets at each location but that will just take a screwdriver to change out.

              By|Oct 10, 2024


                Can this replace a code one model AD smoke detector 120 volt 60 HZ and .05 amps
                ByOct 6, 2024
                1 Answer | 
                Answer This Question

                Hello. No, this alarm is not hardwired. There is no direct replacement for your alarms. That being said, you can use any of the Kidde current hardwired smoke alarms to replace your older alarms. You will have to take down all of the older alarms before putting up any new alarms. You will have to change out and rewire the wiring harness plugs at each location. You will have to change out the mounting brackets at each location but that will just take a screwdriver to change out.

                By|Oct 10, 2024


                  Viewing 1-8 of 182

                  Customer Reviews

                  4.5 out of 5

                  • 4.5 out of 1,718 reviews
                  • 87% recommend this product
                  Filter by:
                  Showing 1-10 of 1,718 reviews
                  I replaced our camper’s outdated smoke detector with this simple and efficient model. Hush button, easy install, comes with an 9 volt battery, and you can’t beat the price!!
                  by
                  • Verified Purchase
                  1 found this review helpful
                  This alarm is small in size but works very well and above all it is of very good quality.
                  by
                  • Verified Purchase
                  1 found this review helpful
                  Cross your fingers
                  Plugged it in, and it didn’t give me a headache immediately, not sure I can really say if it works or not, as my house has not had a fire. I can say it was easy to buy, and easy to install.
                  by
                  • Verified Purchase
                  2 found this review helpful
                  tested with actual smoke and they work!
                  These smoke detectors are smaller than the Kidde ones from a decade ago. (See photo with ruler) The brackets have holes so you can use a string or wire to hang the detector from a nail instead of screwing the bracket to the wall or ceiling. I tested all four of these detectors that I bought and all four detected smoke. The brackets are easy to install. I wrote the installation date on the fronts of some of the detectors so I can reference it easily. Had them for a day, so far so good.
                  by
                    • Recommended
                    6 found this review helpful
                    I just bought these 9 months ago. Today, I walked into my house and the alarm was going off. Worr...
                    I just bought these 9 months ago. Today, I walked into my house and the alarm was going off. Worried, holding my baby, I immediately left my house and called the fire department. These detectors or "defectors" are old and from 2014! I definitely didn't get my money's worth out of them. Extremely disappointed!
                    by
                    Response from Kidde ExpertJun 25, 2020
                    Hello. Call us at Kidde Safety at 1-800-880-6788 with the alarm in hand or contact us on the Kidde website under the Support Tab and choose submit a question. Let us resolve the issues you are having with our products.
                      6 found this review helpful
                      This Kidde Battery Operated Smoke Detector met our needs perfectly. Easy to install. Great price ...
                      This Kidde Battery Operated Smoke Detector met our needs perfectly. Easy to install. Great price and product all the way around.
                      by
                      • Verified Purchase
                      • Recommended
                      6 found this review helpful
                      axcellent product very practical and economical and easy to install
                      axcellent product very practical and economical and easy to install
                      by
                      • Verified Purchase
                      • Recommended
                      2 found this review helpful
                      great price and work great. Easy to mount. I like the blinking led light which isn't too often to...
                      great price and work great. Easy to mount. I like the blinking led light which isn't too often to be annoying. Comes with everything you need.
                      by
                      • Verified Purchase
                      • Recommended
                      4 found this review helpful
                      Easy to install, I like the smaller size so not too obtrusive, great price.
                      Easy to install, I like the smaller size so not too obtrusive, great price.
                      by
                      • Verified Purchase
                      • Recommended
                      2 found this review helpful
                      Slightly smaller in diameter than the usual ones, but works just as well.
                      Slightly smaller in diameter than the usual ones, but works just as well.
                      by
                      • Verified Purchase
                      • Recommended
                      3 found this review helpful
                      Showing 1-10 of 1,718 reviews