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Led lights indicate the alarm's status, with a voice warning to indicate which type of threat is present; a Hush feature silences nuisance alarms, while the end-of-life alert lets you know when it's time to replace the unit.

Keep your family safe with this 3-pack of hardwired smoke and carbon monoxide alarm; The battery backup means constant monitoring, even if there's a power failure.
Dust cover. Can connect to other compatible BRK or First Alert detectors, to ensure all alarms will sound when threat is detected. Features an electrochemical carbon monoxide sensing technology as well as an ionization sensor that detects the fine particles of a fast-burning fire.


Ul certified, 10-year limited warranty. Photoelectric & electrochemical sensor technologies - smoke detector detects invisible fire particles, while the carbon monoxide detects poisonous carbon monoxide gas; 85 decibel alarm alerts of fire.

10-year battery: the fire and co alarm is built with a sealed lithium battery that provides 10 years of continuous power, saving you from changing batteries and power outage.
Led indicator: 3-colored led indicator flashes red, green, or yellow to show the alarm’s working status. 2-in-1 protection: the combination smoke and CO detector detects both smoke and carbon monoxide faster and more accurately using a photoelectric smoke sensor and an electrochemical CO sensor.

Keep your family safer with this hardwired smoke and carbon monoxide alarm; The 10 year battery backup means constant monitoring for the life of the alarm 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. Rigorously tested to meet UL standards, Emits T3 pattern.

High accuracy and sensitivity: x-sense carbon monoxide fire alarm is equipped with combination photoelectric smoke and electrochemical CO sensors that work independently of each other; instantly notifies you when dangerous smoke or CO concentration is detected; provides the ultimate protection from 2 deadly threats, all contained in 1 unit.
10-year battery life: this combination smoke alarm and carbon monoxide alarm provides 10 years of continuous power with a built-in lithium battery; provides continuous monitoring of smoke and CO levels, even if there's a power failure; an end-of-life signal will let you know when it’s time to replace the unit for safety. Easy installation with quality: x-sense smoke carbon monoxide alarm combo requires no rewiring; easy to mount on any wall or ceiling without an electrician; all X-SENSE carbon monoxide alarm and smoke alarm are rigorously tested to meet UL 217 and UL 2034 safety standards; comes with a lifetime customer support. 8 seconds and the red LED flashes with the alarm sound.

Test-hush feature - silences the unit for approximately 9 minutes; tamper-resistant technology deters removal of the unit from the wall or ceiling. 120v ac, all kidde brand hard wired smoke alarms are interconnectable with the KN-COSM-IBA.


Ul certified, 10-year limited warranty. Fire & co detector in 1 unit with alert modes, LED light, test-silence button, & Replacement Alert: a chirp that notifies when the unit needs to be replaced.
1. Kidde
#ad
Kidde Smoke & Carbon Monoxide Detector, Hardwired with 10-Year Battery Backup, Voice Warning
#adKidde #ad - Hardwired alarm contains a 10-year tamper proof backup battery to protect your home and family during power outages, eliminates the need for battery replacement.Led lights indicate the alarm's status, with a voice warning to indicate which type of threat is present; a Hush feature silences nuisance alarms, while the end-of-life alert lets you know when it's time to replace the unit.
More information #ad
Ul certified, 10-year limited warranty. Smart interconnect allows you to connect up to 24 Kidde devices, giving you trusted protection throughout your home. Intelligent technology – smoke and carbon monoxide detector combines ionization & electrochemical sensors to detect invisible fire particles & CO gas; 85dB alarm and voice warning sound when hazard is detected.Brand | Kidde #ad |
Manufacturer | Kidde Safety #ad |
Height | 5.5 Inches |
Length | 5.5 Inches |
Width | 1.5 Inches |
Part Number | 21029756 |
Model | i12010SCO |
Warranty | 10 year limited warranty |
More information #ad
2. FIRST ALERT
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White, FIRST ALERT BRK SC9120B-3 Hardwired Smoke and Carbon Monoxide CO Detector with Battery Backup. 3-Pack
#adFIRST ALERT #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. 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 3-pack of hardwired smoke and carbon monoxide alarm; The battery backup means constant monitoring, even if there's a power failure.
More information #ad
Faster turnarounds on job sites with the easy-to-install, most-trusted alarms in home safety. 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. Dust cover. Can connect to other compatible BRK or First Alert detectors, to ensure all alarms will sound when threat is detected. Features an electrochemical carbon monoxide sensing technology as well as an ionization sensor that detects the fine particles of a fast-burning fire.
Brand | FIRST ALERT #ad |
Manufacturer | First Alert #ad |
Height | 2.2 Inches |
Length | 5.6 Inches |
Weight | 0.7 Pounds |
Width | 5.6 Inches |
Part Number | SC9120BFF-3 |
Model | BRK SC9120B-3 |
More information #ad
3. Kidde
#ad
Battery Powered, Voice Alert, Kidde Smoke & Carbon Monoxide Detector, Combination Smoke & CO Alarm
#adKidde #ad - Ionization sensor technology - smoke detector detects invisible fire particles, 85 decibel alarm alerts of fire. Ul certified, 10-year limited warranty. Protects during a power failure - combo smoke and CO alarm operates on 2-AA batteries.More information #ad
Fire. That states, LED lights, "Warning. Carbon Monoxide. And voice alarm, or "Low Battery. ". Fire and co detector in 1 unit with alert modes, "fire. Test-hush feature - silences the unit for approximately 8 minutes; tamper-resistant technology deters removal of the unit from the wall or ceiling.Brand | Kidde #ad |
Manufacturer | Kidde Safety #ad |
Height | 5.6 Inches |
Length | 1.8 Inches |
Weight | 0.8 Pounds |
Width | 5.6 Inches |
Part Number | 21026043 |
Model | KN-COSM-BA |
Warranty | 5-year limited warranty |
More information #ad
4. Kidde
#ad
Combination Smoke & CO Alarm with Voice Alert, Lithium Battery Powered, Kidde Smoke & Carbon Monoxide Detector
#adKidde #ad - Test-hush feature - silences the unit for approximately 8 minutes; tamper-resistant technology deters removal of the unit from the wall or ceiling.Ul certified, 10-year limited warranty. Photoelectric & electrochemical sensor technologies - smoke detector detects invisible fire particles, while the carbon monoxide detects poisonous carbon monoxide gas; 85 decibel alarm alerts of fire.
More information #ad
Fire & co detector in 1 unit with alert modes, "warning! carbon Monoxide!", & voice alarm, "Fire! Fire!", that states, LED lights, or "Low Battery!". Protects during a power failure - combo smoke and CO alarm operates on a sealed, lithium battery.Brand | Kidde #ad |
Manufacturer | Kidde Safety #ad |
Height | 5.22 Inches |
Length | 5.22 Inches |
Width | 1.6 Inches |
Part Number | 21026065 |
Model | P3010CU |
Warranty | 10 year limited |
More information #ad
5. X-Sense
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Auto-Check, Complies with UL 217 & UL 2034 Standards, X-Sense 10-Year Battery Smoke and Carbon Monoxide Detector Alarm Not Hardwired with LCD Display, 5-Pack, Dual Sensor Fire and CO Alarm
#adX-Sense #ad - Etl listed: this smoke and carbon monoxide detector has been approved by the ETL and meets UL 217 and UL 2034 safety standards. Assured after-sales services: X-Sense offers a 60-day money-back guarantee, a 5-year warranty, and lifetime customer support.10-year battery: the fire and co alarm is built with a sealed lithium battery that provides 10 years of continuous power, saving you from changing batteries and power outage.
More information #ad
Combination alarm with co readings: The informative LCD will show you the battery level and real-time CO levels in PPM parts per million. Simple installation: requires no rewiring; easy to mount this smoke and carbon monoxide alarm on any wall or ceiling with the included mounting bracket, screws, and anchor plugs. Led indicator: 3-colored led indicator flashes red, green, or yellow to show the alarm’s working status. 2-in-1 protection: the combination smoke and CO detector detects both smoke and carbon monoxide faster and more accurately using a photoelectric smoke sensor and an electrochemical CO sensor.
Brand | X-Sense #ad |
Manufacturer | X-Sense #ad |
More information #ad
6. FIRST ALERT
#ad
First Alert BRK SC9120LBL Hardwired Smoke and Carbon Monoxide CO Detector with 10 Year Sealed Battery Backup , White
#adFIRST ALERT #ad - Faster turnarounds on job sites with the easy-to-install, most-trusted alarms in home safety. 10-year limited warranty; equipped with end-of-life signal chirp, so you know when it’s time to replace the unit for safety. 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 safer with this hardwired smoke and carbon monoxide alarm; The 10 year battery backup means constant monitoring for the life of the alarm even if there's a power failure.
More information #ad
Simple to use, with a single test/silence button; Included 10 year lithium battery features a locked drawer to prevent tampering. Features an electrochemical carbon monoxide sensing technology as well as intelligent smoke sensing technology to reduce nuisance alarms; Keyhole slots in the mounting bracket eliminate the need to remove the electrical box screws for installation. 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. Rigorously tested to meet UL standards, Emits T3 pattern.
Brand | FIRST ALERT #ad |
Manufacturer | First Alert #ad |
Height | 5.69 Inches |
Length | 5.59 Inches |
Weight | 0.68 Pounds |
Width | 2.25 Inches |
Part Number | SC9120LBL |
Model | BRK SC9120LBL |
Warranty | 7 |
More information #ad
7. X-Sense
#ad
Dual Sensor Smoke CO Alarm Complies with UL 217 & UL 2034 Standards, Auto-Check, SC03, X-Sense 10-Year Battery Not Hardwired Combination Smoke and Carbon Monoxide Detector Alarm
#adX-Sense #ad - Simple to use: the test/silence button of this smoke alarm carbon monoxide alarm enables you to test the alarm weekly, an alarm tone of over 85 dB will instantly alert the entire household, and to easily silence the alarm when false alarms occur; malfunction and low battery warnings allow you to easily know the working status of the alarm; in case of an emergency, even those in sleep.High accuracy and sensitivity: x-sense carbon monoxide fire alarm is equipped with combination photoelectric smoke and electrochemical CO sensors that work independently of each other; instantly notifies you when dangerous smoke or CO concentration is detected; provides the ultimate protection from 2 deadly threats, all contained in 1 unit.
More information #ad
Alarm types for more convenient: different alarm patterns of this carbon monoxide alarm and smoke alarm tell you it is either smoke or carbon monoxide is detected without checking the LCD display; smoke alarm: delivers 3 long beeps every 1. 5 seconds and the red led flashes with the alarm sound; CO alarm: delivers 4 quick beeps every 5. 10-year battery life: this combination smoke alarm and carbon monoxide alarm provides 10 years of continuous power with a built-in lithium battery; provides continuous monitoring of smoke and CO levels, even if there's a power failure; an end-of-life signal will let you know when it’s time to replace the unit for safety. Easy installation with quality: x-sense smoke carbon monoxide alarm combo requires no rewiring; easy to mount on any wall or ceiling without an electrician; all X-SENSE carbon monoxide alarm and smoke alarm are rigorously tested to meet UL 217 and UL 2034 safety standards; comes with a lifetime customer support. 8 seconds and the red LED flashes with the alarm sound.
Brand | X-Sense #ad |
Manufacturer | X-Sense #ad |
Height | 2 Inches |
Length | 5.7 Inches |
Weight | 0.68 Pounds |
Width | 5.7 Inches |
Part Number | SC03 |
Model | SC03 |
Warranty | 60-day money-back guarantee, 5-year quality warranty, and lifetime technical support |
More information #ad
8. Kidde
#ad
Voice Alert, Hardwired, Interconnect Combination Smoke & CO Alarm with Battery Backup, Kidde Smoke & Carbon Monoxide Detector
#adKidde #ad - Meets safety standards set by Underwriters Laboratories UL and interconnects with other KN-COSM-IBA models. Protects during a power failure - combo smoke and CO detector operates on a 120VAC power source with 2-AA battery backup.Test-hush feature - silences the unit for approximately 9 minutes; tamper-resistant technology deters removal of the unit from the wall or ceiling. 120v ac, all kidde brand hard wired smoke alarms are interconnectable with the KN-COSM-IBA.
More information #ad
Ul certified, 10-year limited warranty. Fire & co detector in 1 unit with alert modes, "warning! Carbon Monoxide!", "Fire! Fire!", LED lights, & voice alarm, that states, or "Low Battery!". Ionization sensing technology - hardwired smoke detector detects invisible fire particles, 85 decibel alarm alerts of fire.Brand | Kidde #ad |
Manufacturer | Kidde Safety #ad |
Height | 6 Inches |
Length | 2 Inches |
Weight | 1 Pounds |
Width | 6 Inches |
Part Number | 21026041 |
Model | KN-COSM-IBA |
Warranty | 10 Year Limited |
More information #ad
9. Kidde
#ad
Voice Alert, Hardwired, Kidde Smoke & Carbon Monoxide Detector, Interconnect Combination Smoke & CO Alarm with Battery Backup
#adKidde #ad - Fire & co detector in 1 unit with alert modes, & voice alarm, "Fire! Fire!", LED lights, that states, "warning! carbon Monoxide!", or "Low Battery!". Photoelectric sensor technology - hardwired smoke detector detects visible fire particles, 85 decibel alarm alerts of fire.More information #ad
Protects during a power failure - combo smoke and CO detector operates on a 120V power source with 9V front-loading battery backup. Test-hush feature - silences the unit for approximately 8 minutes; tamper-resistant technology deters removal of the unit from the wall or ceiling. Ul certified, 10-year limited warranty.Brand | Kidde #ad |
Manufacturer | Kidde Safety #ad |
Height | 1.85 Inches |
Length | 5.79 Inches |
Weight | 0.7 Pounds |
Width | 5.79 Inches |
Part Number | 21029735 |
Model | KN-COPE-IC |
Warranty | 7 year limited |
More information #ad
10. Kidde
#ad
Combination Smoke & CO Alarm with Lithium Battery, Replacement Alert, Kidde Smoke & Carbon Monoxide Detector
#adKidde #ad - Photoelectric & electrochemical sensing technology - combination smoke & CO detector detects visible fire particles, 85 decibel alarm alerts of fire.Ul certified, 10-year limited warranty. Fire & co detector in 1 unit with alert modes, LED light, test-silence button, & Replacement Alert: a chirp that notifies when the unit needs to be replaced.
More information #ad
Replacement alert - can be silenced for 3 days at a time, maximum of 30 days; tamper-resistant technology deters removal of the unit or battery from the wall or ceiling. No battery replacement needed - combo smoke and CO detector operates on a non-replaceable, 10-year lithium battery.Brand | Kidde #ad |
Manufacturer | Kidde Safety #ad |
Height | 1.6 Inches |
Length | 5.22 Inches |
Weight | 0.31 Pounds |
Width | 5.22 Inches |
Part Number | 21010170 |
Model | P3010k-CO |
Warranty | 10 year limited warranty |
More information #ad