First Alert SA521CN-3ST Onelink Wireless Hardwired Smoke Alarm

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Walmart #: 001182558
First Alert SA521CN-3ST Onelink Wireless Hardwired Smoke Alarm
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  • Easily link alarms throughout your house
  • One alarm sounds and all other alarms are notified
  • Photoelectric smoke sensor reduces nuisance alarms
  • About this item

    Important Made in USA Origin Disclaimer: For certain items sold by Walmart on Walmart.com, the displayed country of origin information may not be accurate or consistent with manufacturer information. For updated, accurate country of origin data, it is recommended that you rely on product packaging or manufacturer information.
      Wirelessly interconnect alarms. 120VAC hardwired wireless interconnect smoke alarm with battery backup. To expand protection to include both existing hardwired alarms and new wireless alarms, simply replace one existing hardwired alarm with Onelink, then add Onelink battery operated alarms elsewhere and when one alarm in either series alarms, all alarms will be notified. Easily link alarms together with the press of a button. When one alarm sounds, they all sound for maximum whole home protection. Photoelectric smoke sensor reduces nuisance alarms from cooking smoke or shower steam. Easy access battery drawer: no need to remove alarm from ceiling to change battery. 10-year limited warranty. Meets UL standards.

    About this item

    Important Made in USA Origin Disclaimer: For certain items sold by Walmart on Walmart.com, the displayed country of origin information may not be accurate or consistent with manufacturer information. For updated, accurate country of origin data, it is recommended that you rely on product packaging or manufacturer information.

      Wirelessly interconnect alarms. 120VAC hardwired wireless interconnect smoke alarm with battery backup. To expand protection to include both existing hardwired alarms and new wireless alarms, simply replace one existing hardwired alarm with Onelink, then add Onelink battery operated alarms elsewhere and when one alarm in either series alarms, all alarms will be notified. Easily link alarms together with the press of a button. When one alarm sounds, they all sound for maximum whole home protection. Photoelectric smoke sensor reduces nuisance alarms from cooking smoke or shower steam. Easy access battery drawer: no need to remove alarm from ceiling to change battery. 10-year limited warranty. Meets UL standards.

      120v ac hardwired, easily replace one existing hardwired alarm with Onelink SA521 and then add Onelink battery operated alarms to connect wireless alarms with hardwired alarms--when one sounds, they all sound
    • Battery backup, provides consistent protection for added safety during power outages
    • Photoelectric smoke sensing, optimal protection from smoldering fires
    • Reduces false alarms like those caused by cooking fires and shower steam
    • Mute button, mutes unnecessary alarms immediately. also tests alarm function with same button
    • Eco-friendly, completely recyclable as an electronic device
    • EZ access battery door, no need to remove alarm from ceiling to change battery
    • Optional theft-prevention lock, when activated, batteries and/or alarm cannot be removed without proper tools
    • 2AA batteries included
    • Loud 85db alarm
    • 10-year limited warranty
    • Smoke alarms should be replaced every 10 years for maximum protection
    • Meets UL217 standard
    • FCC compliant.

    Explore this item

    Specifications

    Color: White
    Fabric Content: 100% Multi
    Condition: New
    Size: EA
    Material: Multi
    Manufacturer Part Number: SA521CN-3ST
    Model: SA521CN-3ST
    Brand: First Alert
    Assembled Product Dimensions (L x W x H): 5.00 x 2.00 x 5.00 Inches
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    Comparison Table

    Brand Image
    Power Source
    Power Source
    Sensor Type
    Sensor Type
    Test/Silence Button
    Test/Silence Button
    Dual Smoke and Carbon Monoxide Alarm
    Dual Smoke and Carbon Monoxide Alarm
    Multi-Pack Available
    Multi-Pack Available
    You are viewing
    First Alert Wireless Onelink Smoke and Fire Detector SA521CN-3ST
     
    2-AA, Wireless Enabled
    2-AA, Wireless Enabled
     
    Photoelectric
    Photoelectric
     
    Yes
    Yes
     
     
    First Alert 10-Year Tamper-Proof Smoke and Fire Detector SA340CN
     
    10-Year Lithium
    10-Year Lithium
     
    Ionization
    Ionization
     
    Yes
    Yes
     
     
    First Alert Wireless Onelink Talking Smoke & Fire Detector, 2-Pack SA511CN2-3ST
     
    2-AA, Wireless Enabled
    2-AA, Wireless Enabled
     
    Photoelectric
    Photoelectric
     
    Yes
    Yes
     
     
    First Alert Photoelectric AC/DC Smoke Alarm SA710BPCN
     
    9-Volt
    9-Volt
     
    Photoelectric
    Photoelectric
     
    Yes
    Yes
     
     
    First Alert Photoelectric Smoke Alarm SA710CN
     
    9-Volt
    9-Volt
     
    Photoelectric
    Photoelectric
     
    Yes
    Yes
     
     
    First Alert Photoelectric Smoke and Fire Detector SA720CN
     
    9-Volt
    9-Volt
     
    Photoelectric
    Photoelectric
     
    Yes
    Yes
     
     
    First Alert Hard Wired Smoke Detector and Alarm With Adapter Kit SA9120BPCN
     
    9-Volt
    9-Volt
     
    Ionization
    Ionization
     
    Yes
    Yes
     
     
    First Alert Talking Smoke Alarm and Carbon Monoxide Combination Detector SCO7CN
     
    2-AA
    2-AA
     
    Photoelectric
    Photoelectric
     
    Yes
    Yes
     
    Yes
    Yes
     
    Yes
    Yes
    First Alert Talking Smoke/Fire Alarm and Carbonmoxide Alarm - Child SCO7CN-C
     
    2-AA
    2-AA
     
    Photoelectric
    Photoelectric
     
    Yes
    Yes
     
    Yes
    Yes
     
    Yes
    Yes
    First Alert Smoke and Carbon Monoxide Alarm Combo Package SCO403
     
    2-AA, 1-9V
    2-AA, 1-9V
     
    Ionization
    Ionization
     
    Yes
    Yes
     
    Yes
    Yes
     
    Show

    Manuals & Guides

    Customer Reviews

    Customer Reviews | 8 reviews | 4.6 out of 5

    4.5 stars

    8 reviews | 4.6 out of 5

    4.5 stars

    8 reviews | 4.6 out of 5

    100%
    Would recommend to a friend
    5 stars
    5
    4 stars
    3
    3 stars
    0
    2 stars
    0
    1 stars
    0
    1-8 of 8 total reviews
    100%
    Would recommend to a friend

    Age

    Gender

    Hooked these up at Gram's.
    9/22/2016

    Customer review by Reggie

    4.0 stars 9/22/2016 by Reggie
    by Reggie
    Verified purchaser
    Verified purchaser
    Customer has been confirmed to have purchased the item from Walmart.

    Gram loved that they sent a signal to the rest.

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    Reggie
    Would recommend to a friend? Yes
    Verified purchaser
    Verified purchaser
    Customer has been confirmed to have purchased the item from Walmart.
    Announces Location of the Fire
    8/27/2016

    Customer review by Mouse1999

    5.0 stars 8/27/2016 by Mouse1999
    by Mouse1999
    Verified purchaser
    Verified purchaser
    Customer has been confirmed to have purchased the item from Walmart.

    The original wired smoke alarm that the builder of the home finally failed and so I was happy to find a First Alert One-Link alarm that was wired to replace it. Previously, we installed battery operated ones in each bedroom, garage and laundry room (laundry room has carbon monoxide also as it is right next to the garage.) So after you press some buttons on one of the alarms, all of the alarms will annouce a fire and the location of the fire.

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    Mouse1999
    Would recommend to a friend? Yes
    Verified purchaser
    Verified purchaser
    Customer has been confirmed to have purchased the item from Walmart.
    Being prepared for an unwanted fire...
    1/20/2013

    Customer review by rfg2

    5.0 stars 1/20/2013 by rfg2
    by rfg2
    Verified purchaser
    Verified purchaser
    Customer has been confirmed to have purchased the item from Walmart.

    Being prepared for an unwanted fire is what these devices do. Being in one room sleeping and not hearing a smoke alarm in another room is what could happen. The Con: If other people in near by residents owning similar devices have these alarms that would affect the alarms in your resident. The device does have the ability to by pass the wireless mode and be wired together using the same fuse circuit. That would be a hassle to do, it does have that capability.

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    rfg2
    chicago
    Would recommend to a friend? Yes
    Age:65 or older
    Ownership:2 - 7 weeks
    Gender:Male
    Usage:Every day
    Verified purchaser
    Verified purchaser
    Customer has been confirmed to have purchased the item from Walmart.
    With better instuctions it would be excellent
    2/19/2009

    Customer review by JoeandGlo

    4.0 stars 2/19/2009 by JoeandGlo
    by JoeandGlo

    A very practical way to protect rooms that were not wired into an already built-in smoke alarm system. Worked very well. Instructions need improvement. On testing the units all seem to have a slightly different sound producing a symphony of alerts.

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    JoeandGlo
    State College, PA
    Would recommend to a friend? Yes
    Age:65 or older
    Ownership:3 - 4 months
    Gender:Male
    Usage:A few times per year
    my smoke alarm
    4/5/2016

    Customer review by kenphilr

    5.0 stars 4/5/2016 by kenphilr
    by kenphilr

    vary easy install where my previous smoke detector was. clear instructions. Very good that batteries were included. I'm very pleased that it has battery backup

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    kenphilr
    Would recommend to a friend? Yes
    great alternative to hard wiring
    6/15/2013

    Customer review by Smokeybee

    5.0 stars 6/15/2013 by Smokeybee
    by Smokeybee
    Verified purchaser
    Verified purchaser
    Customer has been confirmed to have purchased the item from Walmart.

    Excellent for extending existing smoke system. Easy programming.

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    Smokeybee
    Daytona Beach, Florida
    Would recommend to a friend? Yes
    Age:45 - 54
    Ownership:2 - 7 weeks
    Gender:Male
    Usage:Every day
    Verified purchaser
    Verified purchaser
    Customer has been confirmed to have purchased the item from Walmart.
    Used with home automation
    11/10/2014

    Customer review by mxsabino

    5.0 stars 11/10/2014 by mxsabino
    by mxsabino

    Connected this to my Insteon system using the Insteon Smoke Bridge. All the Insteon modules connect through my Insteon Hub. This First Alert unit coupled with my Insteon system is better and less expensive than NEST. Very happy with how it works.

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    mxsabino
    Would recommend to a friend? Yes
    Very easy installation
    9/3/2014

    Customer review by brodeurgd

    4.0 stars 9/3/2014 by brodeurgd
    by brodeurgd
    Verified purchaser
    Verified purchaser
    Customer has been confirmed to have purchased the item from Walmart.

    Awesome

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    brodeurgd
    essex junction vt
    Would recommend to a friend? Yes
    Age:45 - 54
    Ownership:1 week or less
    Gender:Male
    Usage:Never
    Verified purchaser
    Verified purchaser
    Customer has been confirmed to have purchased the item from Walmart.

    Customer Reviews | 8 reviews | 4.6 out of 5

    Customer Reviews

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    Customer Q&A

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    Questions & Answers 6 questions
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    Back
    by an anonymous customer 12/25/2009
    4 answers
    • A. Hardwired means it needs to be wired to electricity for power; it has a battery as a backup also. It communicates to other First Alert One Link Alarms wirelessly, but you have to program each alarm with its location. Follow the written directions precisely.
      by Mouse19998/27/2016
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    • A. This unit IS hardwired to a 120 vac circuit breaker protected circuit. The battery is for continued smoke detection during temporary AC power outages. There is also a connection provided to interconnect this unit with other existing hardwired units inside the home. That way all units sound off at the same time when any one unit detects smoke.
      by TekGeezer3/10/2015
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    • A. There is one master unit. All the rest are linked by radio. If any one detects smoke they all go on.
      by JoeandGlo3/10/2015
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    • A. No, these are wireless units that send the signal to each other over the air, IF in range of one other unit. I don't think this unit is a hard wire, even though it implies it above. The reason being is I checked the description of the model number on the manufacturers website and read the manual. It only mentioned putting in the battery, not running electrical wires to it.
      by NyleL6/25/2016
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    Warranty Information: 10-Year Limited
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