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Can connect to other compatible BRK or First Alert detectors, to ensure all alarms will sound when threat is detected.
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. Faster turnarounds on job sites with the easy-to-install, most-trusted alarms in home safety. Dust cover.

Meets safety standards set by Underwriters Laboratories UL and interconnects with other KN-COSM-IBA models. Ul certified, 10-year limited warranty. Test-hush feature - silences the unit for approximately 9 minutes; tamper-resistant technology deters removal of the unit from the wall or ceiling.


Smart interconnect allows you to connect up to 24 Kidde devices, giving you trusted protection throughout your home. 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.


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.
Rigorously tested to meet UL standards, Emits T3 pattern. Simple to use, with a single test/silence button; Included 10 year lithium battery features a locked drawer to prevent tampering. 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 accurate with intelligent technology: this hardwired smoke alarm and carbon monoxide detector combines an advanced photoelectric smoke sensor and a Figaro electrochemical CO sensor to detect smoke from smoldering fires and dangerous CO levels quickly.
Easy installation: All mounting hardware is included for fast and simple installation in minutes. Hardwired alarm with replaceable battery backup: this combination smoke and carbon monoxide detector is AC hardwired with a 9 V battery backup, so the alarm can continuously monitor for smoke and CO even if there is a power outage.


If the alarm has detected a co level of 100ppm or greater, when the test/reset button is pressed the unit will announce “CO previously detected”. Fire warning - the red led will flash and be accompanied by three long alarm beeps followed by a verbal warning message “Fire Fire” The alarm will repeat pattern until unit is reset or smoke is eliminated.
Ac-wire with battery backup, An included 9V battery protects during short-term power outages. The “low battery” warning will only sound once every fifteen minutes. If the alarm has detected abnormal levels of smoke since its last test, it will produce three rapid beeps. Alarm memory - the green led will blink once every 16 seconds to alert a user when the unit has alarmed for smoke or has detected a concentration of CO. The red led light will flash.
1. FIRST ALERT
#ad
FIRST ALERT BRK SC9120B-3 Hardwired Smoke and Carbon Monoxide CO Detector with Battery Backup. 3-Pack , White
#adFIRST ALERT #ad - 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. 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.Can connect to other compatible BRK or First Alert detectors, to ensure all alarms will sound when threat is detected.
More information #ad
Features an electrochemical carbon monoxide sensing technology as well as an ionization sensor that detects the fine particles of a fast-burning fire. 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, and side-load battery compartment; Tamper-resistant locking brackets and universal mounting brackets make installation easy. Faster turnarounds on job sites with the easy-to-install, most-trusted alarms in home safety. Dust cover.
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
2. Kidde
#ad
Kidde Smoke & Carbon Monoxide Detector, Hardwired, Interconnect Combination Smoke & CO Alarm with Battery Backup, Voice Alert
#adKidde #ad - Ionization sensing technology - hardwired smoke detector detects invisible fire particles, 85 decibel alarm alerts of fire. 120v ac, all kidde brand hard wired smoke alarms are interconnectable with the KN-COSM-IBA.Meets safety standards set by Underwriters Laboratories UL and interconnects with other KN-COSM-IBA models. Ul certified, 10-year limited warranty. Test-hush feature - silences the unit for approximately 9 minutes; tamper-resistant technology deters removal of the unit from the wall or ceiling.
More information #ad
Protects during a power failure - combo smoke and CO detector operates on a 120VAC power source with 2-AA battery backup. Fire & co detector in 1 unit with alert modes, led lights, that states, & voice alarm, "Fire! Fire!", "Warning! Carbon Monoxide!", or "Low Battery!".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
3. Kidde
#ad
Kidde Smoke & Carbon Monoxide Detector, Voice Alert, Hardwired, Interconnect Combination Smoke & CO Alarm with Battery Backup
#adKidde #ad - Photoelectric sensor technology - hardwired smoke detector detects visible fire particles, 85 decibel alarm alerts of fire. Test-hush feature - silences the unit for approximately 8 minutes; tamper-resistant technology deters removal of the unit from the wall or ceiling.More information #ad
Ul certified, 10-year limited warranty. Fire & co detector in 1 unit with alert modes, & voice alarm, "Fire! Fire!", that states, LED lights, "Warning! Carbon Monoxide!", or "Low Battery!". Protects during a power failure - combo smoke and CO detector operates on a 120V power source with 9V front-loading battery backup.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
4. Kidde
#ad
Voice Warning, Kidde Smoke & Carbon Monoxide Detector, Hardwired with 10-Year Battery Backup
#adKidde #ad - 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.Smart interconnect allows you to connect up to 24 Kidde devices, giving you trusted protection throughout your home. 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. 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.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
5. Kidde
#ad
Pack of 2, Voice Alert, Hardwired, Kidde Smoke & Carbon Monoxide Detector, Interconnect Combination Smoke & CO Alarm with Battery Backup
#adKidde #ad - Test-hush feature - silences the unit for approximately 9 minutes; tamper-resistant technology deters removal of the unit from the wall or ceiling. Fire & co detector in 1 unit with alert modes, led lights, "Warning! Carbon Monoxide!", that states, & voice alarm, "Fire! Fire!", or "Low Battery!".More information #ad
Protects during a power failure - combo smoke and CO detector operates on a 120VAC power source with 2-AA battery backup. Ul certified, 10-year limited warranty. Ionization sensing technology - hardwired smoke detector detects invisible fire particles, 85 decibel alarm alerts of fire.Brand | Kidde #ad |
Manufacturer | Kidde #ad |
Height | 5.6 Inches |
Length | 2.64 Inches |
Weight | 0.75 Pounds |
Width | 1.8 Inches |
Part Number | 900-0114A |
Model | KN-COSM-IBA |
Warranty | 10 year limited manufacturer |
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 - 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. Faster turnarounds on job sites with the easy-to-install, most-trusted alarms in home safety.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.
More information #ad
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. Rigorously tested to meet UL standards, Emits T3 pattern. Simple to use, with a single test/silence button; Included 10 year lithium battery features a locked drawer to prevent tampering. 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.
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
Pack of 3, Hardwired Interconnected Smoke and CO Detector Alarm with Replaceable Battery Backup, XP04, X-Sense Hardwired Combination Smoke and Carbon Monoxide Detector
#adX-Sense #ad - Interconnects up to 24 units for full coverage: you can connect up to 24 X-Sense 2-in-1 hardwired alarms, so when one alarm is triggered, all will sound together throughout your home. Premium quality: made from high-quality materials and components, this smoke detector hardwired combination alarm offers a long lifespan of up to 10 years.More accurate with intelligent technology: this hardwired smoke alarm and carbon monoxide detector combines an advanced photoelectric smoke sensor and a Figaro electrochemical CO sensor to detect smoke from smoldering fires and dangerous CO levels quickly.
More information #ad
Easy installation: All mounting hardware is included for fast and simple installation in minutes. Hardwired alarm with replaceable battery backup: this combination smoke and carbon monoxide detector is AC hardwired with a 9 V battery backup, so the alarm can continuously monitor for smoke and CO even if there is a power outage.
Brand | X-Sense #ad |
Manufacturer | X-Sense #ad |
Height | 1.45 Inches |
Length | 5.5 Inches |
Weight | 0.5 Pounds |
Width | 5.5 Inches |
Model | XP04 |
Warranty | 60-day money-back guarantee, 5-year quality warranty, and lifetime technical support |
More information #ad
8. Kidde
#ad
Voice Warning, Kidde P4010ACS-W P4010 Smoke & Carbon Monoxide Detector, Hardwired with Lithium Battery Backup, White
#adKidde #ad - Hardwired alarm with tamper proof backup battery – to help protect your home and family during power outages, eliminates the need for battery replacement. Hush feature silences nuisance or “false” alarms – with just the push of a button on the alarm itself.More information #ad
Voice warnings – “fire!” so you know why the smoke detector is sounding. Photoelectric sensor technology to detect visible fire particles. 85db alarm and voice warning sound when hazard is detected. Ul certified, 10-year limited warranty.Brand | Kidde #ad |
Manufacturer | Kidde Safety #ad |
Height | 5.59 Inches |
Length | 1.91 Inches |
Weight | 0.6 Pounds |
Width | 5.59 Inches |
Part Number | 21027320 |
Model | P4010ACS-W |
Warranty | 10 year limited |
More information #ad
9. Kidde
#ad
Kidde 21007624 AC Photoelectric Smoke and Carbon Monoxide Detector Alarm | Hardwired with Battery Backup | Model # KN-COPE-IC
#adKidde #ad - This pattern will continue every minute for the first hour. After the first hour the red LED light will flash once every minute accompanied by the chirp sound. Voice hush indication: “hush activated” and “Hush cancelled” voice announcement. Voice warning with green and red LEDs. Tamper resistant.If the alarm has detected a co level of 100ppm or greater, when the test/reset button is pressed the unit will announce “CO previously detected”. Fire warning - the red led will flash and be accompanied by three long alarm beeps followed by a verbal warning message “Fire Fire” The alarm will repeat pattern until unit is reset or smoke is eliminated.
More information #ad
Carbon monoxide warning - four short alarm beeps followed by a verbal warning “Warning, Carbon monoxide” This continues until the unit is reset or the CO is eliminated. Photoelectric smoke sensor – May detect visible fire particles associated with slow smoldering fires sooner than an ionization sensor. Ac-wire with battery backup, An included 9V battery protects during short-term power outages. The “low battery” warning will only sound once every fifteen minutes. If the alarm has detected abnormal levels of smoke since its last test, it will produce three rapid beeps. Alarm memory - the green led will blink once every 16 seconds to alert a user when the unit has alarmed for smoke or has detected a concentration of CO. The red led light will flash.
Brand | Kidde #ad |
Manufacturer | Kidde #ad |
Height | 1.85 Inches |
Length | 5.79 Inches |
Weight | 0.92 Pounds |
Width | 5.79 Inches |
Part Number | 21007624 |
Model | 21007624 |
Warranty | 7 year limited |
More information #ad