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If the unit still does not alarm, replace it immediately. Keep your family safe with this easy to use, battery operated carbon monoxide alarm; Battery powered alarms provide continuous monitoring of CO levels, even if there's a power failure.
The alarm sequence should last 5-6 seconds. If it does not alarm, and test it again. To ensure complete protection make sure to place one on each level of your home and in each bedroom. All first alert cO alarms are rigorously tested to meet UL standards. A loud 85 decibel alarm sounds when CO levels reach dangerous levels.

To ensure complete protection make sure to place one on each level of your home and in each bedroom.
7 year limited warranty; equipped with end of life signal chirp, so you know when it’s time to replace the unit for safety. Simple to use, with a single test/silence button; A loud 85 decibel alarm sounds when carbon monoxide levels reach dangerous levels.

All first alert cO alarms are rigorously tested to meet UL standards. Features an advanced electrochemical carbon monoxide sensor; Peak level feature displays the highest concentration of carbon monoxide measured.
To ensure complete protection make sure to place one on each level of your home and in each bedroom. 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.

Keep your family safe with this easy to use digital-display, 10-year battery operated carbon monoxide alarm; Battery powered alarms provide continuous monitoring of CO levels, even if there's a power failure.
10-year limited warranty; equipped with end-of-life signal chirp, so you know when it’s time to replace the unit for safety. 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.


Low battery signal mute, quiets low battery signal for up to 8 hours. Features an electrochemical carbon monoxide sensing technology as well as a photoelectric sensor that detects the larger particles of a smoldering fire.
Keep your family safe with this battery operated smoke and carbon monoxide alarm; Battery powered alarms provide continuous monitoring of CO levels, even if there's a power failure. 7 year limited warranty; equipped with end of life signal chirp, so you know when it’s time to replace the unit for safety; All first alert alarms are rigorously tested to meet UL standards.

To ensure complete protection make sure to place 1 on each level of your home and in each bedroom. End of life timer; 7 year limited warranty.

Indicator lights on the face of the unit display the presence of smoke or carbon monoxide, while an 85 decibel siren provides a clear, loud warning upon detection.
Keep your family safe with this hardwired smoke and carbon monoxide alarm; The battery backup means constant monitoring, even if there's a power failure. Rigorously tested to meet UL standards. Simple to use, with a single test/silence button, and side load battery compartment; Tamper resistant locking brackets and universal mounting brackets make installation easy.

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.
To ensure complete protection make sure to place one on each level of your home and in each bedroom. A loud 85 decibel alarm sounds when Carbon Monoxide levels reach dangerous levels. 7 year limited warranty; equipped with end of life signal chirp, so you know when it’s time to replace the unit for safety.

1. FIRST ALERT
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Battery Operated Alarm, First Alert CO400 Carbon Monoxide CO Detector, 1-Pack
#adFIRST ALERT #ad - 5-year limited warranty; equipped with end of life signal chirp, so you know when it’s time to replace the unit for safety. 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.If the unit still does not alarm, replace it immediately. Keep your family safe with this easy to use, battery operated carbon monoxide alarm; Battery powered alarms provide continuous monitoring of CO levels, even if there's a power failure.
More information #ad
Features an advanced electrochemical carbon monoxide sensor that accurately detects carbon monoxide levels, make sure fresh batteries are correctly installed, no matter where the detector is placed in the room. The alarm sequence should last 5-6 seconds. If it does not alarm, and test it again. To ensure complete protection make sure to place one on each level of your home and in each bedroom. All first alert cO alarms are rigorously tested to meet UL standards. A loud 85 decibel alarm sounds when CO levels reach dangerous levels.
Brand | FIRST ALERT #ad |
Manufacturer | First Alert #ad |
Height | 3 Inches |
Length | 5 Inches |
Weight | 0.45 Pounds |
Width | 1 Inches |
Part Number | CO400 |
Model | CO400FF |
Warranty | 5 Year Limited Warranty |
More information #ad
2. FIRST ALERT
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First Alert CO605 Plug-In Carbon Monoxide Detector with Battery Backup , White
#adFIRST ALERT #ad - Item length is 3. 4 inches, item width is 1. 38 inches and item height is 5 inches. Low battery signal mute, quiets low battery signal for up to 8 hours. All first alert co alarms are rigorously tested to meet UL standards. 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.To ensure complete protection make sure to place one on each level of your home and in each bedroom.
More information #ad
Features an advanced electrochemical carbon monoxide sensor that accurately detects carbon monoxide levels, no matter where the detector is placed in the room. Keep your family safe with this easy to use plug in carbon monoxide alarm; It works with any standard outlet and also has a battery backup for continuous monitoring of Carbon Monoxide levels, even if there's a power failure. 7 year limited warranty; equipped with end of life signal chirp, so you know when it’s time to replace the unit for safety. Simple to use, with a single test/silence button; A loud 85 decibel alarm sounds when carbon monoxide levels reach dangerous levels.
Brand | FIRST ALERT #ad |
Manufacturer | First Alert #ad |
Height | 5 Inches |
Length | 3.4 Inches |
Weight | 0.26 Pounds |
Width | 1.38 Inches |
Part Number | FATCO605 |
Model | CO605 |
More information #ad
3. FIRST ALERT
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White, First Alert CO615 Dual-Power Plug-In Carbon Monoxide Detector with Battery Backup and Digital Display
#adFIRST ALERT #ad - Keep your family safe with this digital display, plug in carbon monoxide alarm; It works with any standard outlet and also has a battery backup for continuous monitoring of Carbon Monoxide levels, even if there's a power failure.All first alert cO alarms are rigorously tested to meet UL standards. Features an advanced electrochemical carbon monoxide sensor; Peak level feature displays the highest concentration of carbon monoxide measured.
More information #ad
A loud 85 decibel alarm sounds when Carbon Monoxide levels reach dangerous levels. 7 year limited warranty; equipped with end of life signal chirp, so you know when it’s time to replace the unit for safety. To ensure complete protection make sure to place one on each level of your home and in each bedroom. 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.
Brand | FIRST ALERT #ad |
Manufacturer | First Alert #ad |
Height | 5 Inches |
Length | 3.4 Inches |
Weight | 0.29 Pounds |
Width | 1.7 Inches |
Part Number | FATCO615 |
Model | CO615 |
Warranty | 7-year Limited Warranty |
More information #ad
4. FIRST ALERT
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White, First Alert CO710 Carbon Monoxide Detector with 10-Year Battery and Digital Temperature Display
#adFIRST ALERT #ad - A loud 85-decibel alarm sounds when CO levels reach dangerous levels. Built-in 10-year lithium battery offers continuous protection for the life of the carbon monoxide detector. All first alert cO alarms are rigorously tested to meet UL standards.Keep your family safe with this easy to use digital-display, 10-year battery operated carbon monoxide alarm; Battery powered alarms provide continuous monitoring of CO levels, even if there's a power failure.
More information #ad
Easy-to-read backlit digital display shows temperature and CO concentration; Peak Level feature displays the highest concentration of carbon monoxide measured. 10-year limited warranty; equipped with end-of-life signal chirp, so you know when it’s time to replace the unit for safety. 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.
Brand | FIRST ALERT #ad |
Manufacturer | First Alert / BRK Brands, Inc. #ad |
Height | 2.63 Inches |
Length | 0.94 Inches |
Weight | 0.5 Pounds |
Width | 4.75 Inches |
Part Number | CO710 |
Model | CO710 |
More information #ad
5. FIRST ALERT
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White, FIRST ALERT BRK CO5120BN Hardwired Carbon Monoxide CO Detector with Battery Backup
#adFIRST ALERT #ad - Microprocessor controlled to minimize false alarms. Plastic. Electrochemical sensor accurately detects carbon monoxide. Faster turnarounds on job sites with the easy-to-install, most-trusted alarms in home safety.More information #ad
Easy to access battery drawer; 9 volt battery included. Can integrate with up to 18 compatible devices for extended coverage; Emits T3 Pattern. 120 volt hard wired carbon monoxide alarm wires directly into your home's electrical system. Imported.Brand | FIRST ALERT #ad |
Manufacturer | BRK Brands #ad |
Height | 5.72 Inches |
Length | 5.53 Inches |
Weight | 0.55 Pounds |
Width | 2.09 Inches |
Part Number | GID-601054 |
Model | CO5120BN |
Warranty | ------- |
More information #ad
6. FIRST ALERT
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Battery Operated, 1 Pack, White, First Alert Powered Alarm SCO5CN Combination Smoke and Carbon Monoxide Detector
#adFIRST ALERT #ad - Indicator lights on the face of the unit display the presence of smoke or carbon monoxide, while an 85 decibel siren provides a clear, loud warning upon detection. Emits T3 Pattern. It can ship within the US except New York. Battery operated unit installs quickly and easily without an electrician.Low battery signal mute, quiets low battery signal for up to 8 hours. Features an electrochemical carbon monoxide sensing technology as well as a photoelectric sensor that detects the larger particles of a smoldering fire.
More information #ad
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. Simple to use, with a single test/silence button; EZ access battery drawer allows you to change battery without removing alarm from ceiling. Keep your family safe with this battery operated smoke and carbon monoxide alarm; Battery powered alarms provide continuous monitoring of CO levels, even if there's a power failure. 7 year limited warranty; equipped with end of life signal chirp, so you know when it’s time to replace the unit for safety; All first alert alarms are rigorously tested to meet UL standards.
Brand | FIRST ALERT #ad |
Manufacturer | First Alert #ad |
Height | 5 Inches |
Length | 2 Inches |
Weight | 0.6 Pounds |
Width | 5 Inches |
Part Number | SCO5CN |
Model | SCO5CN |
Warranty | ------- |
More information #ad
7. FIRST ALERT
#ad
First Alert CO600 Plug-In Carbon Monoxide Detector
#adFIRST ALERT #ad - Keep your family safe with this easy to use plug in carbon monoxide alarm; It works with any standard outlet. 7 year limited warranty; equipped with end of life signal chirp, so you know when it’s time to replace the unit for safety.To ensure complete protection make sure to place 1 on each level of your home and in each bedroom. End of life timer; 7 year limited warranty.
More information #ad
Features an advanced electrochemical carbon monoxide sensor that accurately detects carbon monoxide levels, no matter where the detector is placed in the room. Uses electrochemical carbon monoxide sensor the most accurate technology available. 120 volt ac plug in carbon monoxide alarm. A loud 85 decibel alarm sounds when carbon monoxide levels reach dangerous levels.Brand | FIRST ALERT #ad |
Manufacturer | First Alert #ad |
Height | 2.8 Inches |
Length | 8.5 Inches |
Weight | 0.3 Pounds |
Width | 6.75 Inches |
Part Number | CO600 |
Model | FATCO600 |
More information #ad
8. FIRST ALERT
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1 pack , White, FIRST ALERT BRK SC9120FF Hardwired Smoke and Carbon Monoxide CO Detector with Battery Backup
#adFIRST ALERT #ad - Features an electrochemical carbon monoxide sensing technology as well as an ionization sensor for smoke detection. 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.Indicator lights on the face of the unit display the presence of smoke or carbon monoxide, while an 85 decibel siren provides a clear, loud warning upon detection.
More information #ad
Faster turnarounds on job sites with the easy-to-install, most-trusted alarms in home safety. Can connect to other compatible BRK or First Alert detectors, to ensure all alarms will sound when threat is detected. Keep your family safe with this hardwired smoke and carbon monoxide alarm; The battery backup means constant monitoring, even if there's a power failure. Rigorously tested to meet UL standards. Simple to use, with a single test/silence button, and side load battery compartment; Tamper resistant locking brackets and universal mounting brackets make installation easy.
Brand | FIRST ALERT #ad |
Manufacturer | First Alert #ad |
Height | 1.9 Inches |
Length | 5.6 Inches |
Weight | 0.25 Pounds |
Width | 5.6 Inches |
Part Number | SC9120B |
Model | SC9120B |
Warranty | 10 Year Limited |
More information #ad
9. FIRST ALERT
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First Alert Carbon Monoxide Detector Alarm|No Outlet Required with Digital Display and Peak Memory, Battery Operated, White, CO410
#adFIRST ALERT #ad - Features an advanced electrochemical carbon monoxide sensor; Peak Level feature displays the highest concentration of carbon monoxide measured. Keep your family safe with this easy to use digital display, battery operated carbon monoxide alarm; battery powered alarms provide continuous monitoring of CO levels, even if there's a power failure.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.
More information #ad
All first alert co alarms are rigorously tested to meet UL standards. To ensure complete protection make sure to place one on each level of your home and in each bedroom. A loud 85 decibel alarm sounds when Carbon Monoxide levels reach dangerous levels. 7 year limited warranty; equipped with end of life signal chirp, so you know when it’s time to replace the unit for safety.
Brand | FIRST ALERT #ad |
Manufacturer | First Alert #ad |
Height | 8.5 Inches |
Length | 2.25 Inches |
Weight | 0.58 Pounds |
Width | 7 Inches |
Part Number | CO410 |
Model | CO410 |
More information #ad
10. FIRST ALERT
#ad
First Alert BRK SC-9120B Hardwired Smoke and Carbon Monoxide CO Detector with Battery Backup
#adFIRST ALERT #ad - 9-volt battery included; 10-year limited warranty. Superior carbon monoxide sensor and dual ionization smoke alarm. Simple to use silence/test button; separate smoke and CO latching alarm indicators.More information #ad
Inter-connectable with BRK and First Alert hardwired smoke and carbon monoxide alarms. Faster turnarounds on job sites with the easy-to-install, most-trusted alarms in home safety. Easy to install universal mount bracket.Brand | FIRST ALERT #ad |
Manufacturer | BRK Brands #ad |
Height | 5.69 Inches |
Length | 5.59 Inches |
Weight | 0.65 Pounds |
Width | 2.25 Inches |
Part Number | SC9120B |
Model | SC9120B |
More information #ad