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First Alert

First Alert SCO501CN-3ST Wireless Interconnected Combination Smoke and Carbon Monoxide Alarm with Voice Location, Battery Operated (pack of 1)

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Arrives Thursday, Mar 12
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Size: 1-pack


Style: Standard Detection


Pattern Name: SCO501CN-3ST


Features

  • The front cover design of the alarm may vary but product function remains the same.
  • Battery operated smoke and carbon monoxide alarm can be installed easily
  • Connects multiple alarms together for wireless safety network
  • Voice alarm gives clear indication of where the problem is located
  • Features photoelectric smoke sensor and electrochemical CO sensor
  • One button silences a false alarm and tests the unit. Loud 85 decibel alarm
  • NOTE: Kindly refer to the user manual provided as a PDF manual in the product description section
  • First Alert has been the most trusted brand in home safety since launching the first residential smoke alarm in 1958 (Based on a First Alert Brand Trust Survey in February 2018)
  • Smoke particles of varying number and size are produced in all fires. For maximum protection, use both ionization and photoelectric sensing technologies. Ionization alarms are generally more sensitive to fast flaming fires and photoelectric alarms are generally more sensitive to smoldering fires

Description

The First Alert SCO501CN 3ST Combination Smoke and Carbon Monoxide Alarm with Voice Location detects both smoke and carbon monoxide in a single device. The alarm interconnects with up to 18 other First Alert enabled alarms in your home to create a wireless safety network. The photoelectric smoke sensor is designed to reduce false alarms from cooking smoke or shower steam while remaining sensitive to real danger. The advanced electrochemical CO sensor detects carbon monoxide leaks from multiple sources, including faulty fuel burning appliances. A loud 85 decibel siren and a voice alarm with 11 programmable locations indicate where and what the threat is. EZ access battery drawer, no need to remove alarm from ceiling to change battery. From the Manufacturer Keep your family safe from both fire and carbon monoxide poisoning with the First Alert ONELINK battery operated combination Smoke and Carbon Monoxide Alarm. ONELINK offers the same interconnected functionality as standard hardwired alarms without wires. The alarms communicate with each other and may provide an earlier warning of potential danger when people are in different locations in the home. The sooner you know, the sooner emergency responders can be notified, this may help reduce the potential loss of life and property damage. When compared to retrofitting an existing home, First Alert ONELINK costs much less than installing hardwired alarms in existing walls and/or ceilings. They are cost effective and easy to install. First Alert Exclusive voice alarm is programmable with up to eleven locations. Additional battery operated alarms may be added to create a wireless safety network. Photoelectric Smoke Sensing Technology reduces nuisance alarms and is environmentally friendlier. The Electrochemical Carbon Monoxide Sensor is the most accurate technology available. Comes complete with Test/Silence Button, Low Battery Warning, two AA Batteries and 5 year warranty.

Brand: First Alert


Style: Standard Detection


Power Source: Battery Powered


Color: White


Product Dimensions: 2"D x 5"W x 5"H


Item Weight: 0.2 Pounds


Alarm: Audible


Sensor Type: electrochemical,photoelectric


Global Trade Identification Number: 57


Material: FIRST ALERT SCO501CN-3ST ONELINK Battery-Operated Combination Smoke & Carbon Monoxide Alarm with


Brand: ‎First Alert


Style: ‎Standard Detection


Power Source: ‎Battery Powered


Color: ‎White


Product Dimensions: ‎2"D x 5"W x 5"H


Item Weight: ‎0.2 Pounds


Alarm: ‎Audible


Sensor Type: ‎electrochemical,photoelectric


Global Trade Identification Number: ‎57


Material: ‎FIRST ALERT SCO501CN-3ST ONELINK Battery-Operated Combination Smoke & Carbon Monoxide Alarm with


Number of Items: ‎1


Manufacturer: ‎First Alert


UPC: ‎029054002457


Part Number: ‎SCO500


Item Weight: ‎3.2 ounces


Item model number: ‎SCO500


Batteries: ‎2 AA batteries required. (included)


Is Discontinued By Manufacturer: ‎No


Size: ‎1-pack


Pattern: ‎SCO501CN-3ST


Voltage: ‎120 Volts


Item Package Quantity: ‎1


Number Of Pieces: ‎1


Included Components: ‎Smoke detector, batteries


Batteries Included?: ‎Yes


Batteries Required?: ‎Yes


Battery Cell Type: ‎Alkaline


Description Pile: ‎Rechargeable lithium-ion battery included.


Warranty Description: ‎7 Year


Date First Available: December 7, 2003


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Thursday, Mar 12

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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Similar Products

Top Amazon Reviews

    • Very Effective, Well Worth the Money
Size: (Pack of 1) Style: Precision Detection Pattern Name: SMCO500V
I have purchased a property that was lacking in the smoke alarm department and had no wireless interconnection and these were the first choice. They are very easy to pair and install. Fair warning though, they are loud. I wore my noise cancelling earbuds and even through those, I can clearly hear them. The quality is good, you can hear them clearly when they give the location of which one went off. These things are also very functional as I had unintentionally set them off less than a couple weeks of installation. They will save your life in a fire. I highly recommend getting these as they are worth the investment. ... show more
Reviewed in the United States on September 17, 2025 by Avexis
    • Easy installation and setup...worked when kitchen got smoky
Size: 1-pack Style: Standard Detection Pattern Name: SCO501CN-3ST
Update: A little cooking accident caused a lot of smoke (no fire). The nearest alarm went off properly, and all of the linked alarms went off as well. Silencing the alarm required holding down the silence button for five seconds or so, which silenced all of the linked alarms. This review is based ONLY on the installation and setup. I just installed 7 units. The installation is very easy...took me about 60 seconds per unit to install the mounting rings.. You'll need a Phillips head screwdriver and a drill with a 3/16 bit for the mounting holes. I'm pretty handy with tools, but there was nothing involved in this that a novice should have difficulty with. Follow the instructions for where they should be mounted. There is a "dead zone" where walls and ceilings meet. Smoke detectors are ineffective in that zone. The previous owner of my home mounted all of the old detectors right in the dead zone. Oops. The programming is easy IF you read the directions and follow them exactly. Women should do fine; men will probably have to try programming a couple times before they figure out which simple step they overlooked. (I got it on the second attempt.) If you are overdue for new bifocals like I am, you might need a magnifying glass. The programming took less than a minute per unit when I did it correctly. Use hearing protection while you are programming and and testing. Seriously. All of the units will be going off at the same time on the table in front of you. At 85 decibels each, it is extremely loud, My total project time for installing all 7 was about 45 minutes hour from opening the box to putting up my tools. My units are spread out over three levels of the house (one in the basement, two on the first floor, one in an upstairs hallway, and one in each of three bedrooms). No issues with them communicating with each other. I tested each one individually and made certain it was communicating with all the others just to be sure. Running up and down all the stairs 7 times was a good workout. Again, hearing protection is advised. I have no doubt we will all be awakened if we ever have a fire in middle of the night. I really like the voice feature. If I have an alarm I will not have to go running through the house to figure out where the problem is. It clearly enunciates which unit is going off. Hopefully I will never find out how they operate in an emergency. I will update if I have any operational issues. ... show more
Reviewed in the United States on January 13, 2014 by stevem
    • Awesome Interconnected Smoke & Carbon monoxide detector (battery unit) with voice
Size: (Pack of 1) Style: Precision Detection Pattern Name: SMCO500V
I've used previous iterations of this Battery operated (Wirelessly Interconnected) Smoke & Carbon Monoxide Detector (w/voice) in the past and this unit (SMCO500V) lives up to its predecessor. It's simple to use and setup (provided instructions are read - to pair the units wirelessly to work together). - They're Loud...but Not too loud - thankfully. - The mounts are a standard design to other smoke detectors (that can screw into the ceiling apparatus) and thus no new mounts were needed to attach these units in my home. - Battery-wise: If these units function like their predecessors - I'm sure it will last for several months on the eneloop AAs which I have been using for smoke detectors over the years. - Battery drawers are easy to pull open and get the batteries out. Simply push upwards from the bottom (of the battery drawer) to release and swap your batteries. - Haven't experienced any false Alarms with these particular units yet...but will update this review if I do. - All in all, a good device that lives up to its predecessor 👍 ... show more
Reviewed in the United States on August 15, 2025 by JW
    • Works great, but with limits
Size: 1-pack Style: Standard Detection Pattern Name: SCO501CN-3ST
These detectors are a great idea. They really do link together and communicate, making a whole house network of smoke detectors. They also use the latest photoelectric sensor type, which was recently recommended by our local news report on smoke detectors. They're supposed to be quicker to sense a fire, plus they have CO2 sensors for a double whammy. I bought four of them, two for the kids' bedrooms, one for the hallway outside the master bedroom, and one for the basement. I had originally thought maybe we could put one each in our unattached garage and horse barn, but after the in-house experiment, I doubt that will work. The first thing I noticed is that, although the battery compartment is conveniently located and designed to allow access without removing the unit(which is nice), not all are assembled equally. Two of them opened really nicely, one a little stiff, and the third I broke two nails and almost my thumb trying to open the battery compartment to insert the AA's (Energizers included). Then I followed the activation instructions one at a time to make sure they communicate. At first they wouldn't work. The first unit said "error" or something like that, "Check owner's manual". Well I realized that I had them on the desk next to my wireless router, so I moved them to the bed in the master bedroom and that cured the problem. While laying side by side, they all communicated effectively. I installed them in two upstairs bedrooms on the walls. One at the foot of the upstairs stairway outside the master bedroom, and one in the basement next to the furnace. At first they all worked great. The test of any unit sounded on all of them. However, when I tested the basement one, it said it had an error. I ended up having to move the basement unit closer to the stairs going up (farther from the furnace) before they all communicated smoothly. Now they're located fairly over top of one another. I think if there's too many walls, and maybe in interfering wireless system, their sensitivity is impaired. It is really cool though to push the test button in the basement and have all units say (in a piercing, painfully loud voice) "EVACUATE! SMOKE DETECTED IN BASEMENT!" after the test announcement. Maybe they're better if a wireless router isn't present, but they're doing the job for now. I really doubt they would reach the garage or barn with the basement issue we had. ... show more
Reviewed in the United States on April 27, 2008 by MBK

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