10 Best Brk Electronics 4120b Replacement of 2025

Main Highlights

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  Superior carbon monoxide sensor and dual ionization smoke alarm
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  Inter-connectable with BRK and First Alert hardwired smoke and carbon monoxide alarms
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  Easy to install universal mount bracket
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  Simple to use silence/test button; separate smoke and CO latching alarm indicators
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  9-volt battery included; 10-year limited warranty
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  Faster turnarounds on job sites with the easy-to-install, most-trusted alarms in home safety

Main Highlights

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  6 pack of hardwired smoke alarms, includes battery backup for power outages
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  Tamper resistant locking pins, single button silence/test and loud 85Db alarm
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  120-Volt AC power with 9-volt battery backup (included) to keep alarm functioning during power outage
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  Open mounting design for easy installation with side load battery compartment for quick replacement and interconnect able up to 18 units (12 smoke, 6 co/heat/relay)
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  10-Year limited
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  Faster turnarounds on job sites with the easy-to-install, most-trusted alarms in home safety

Main Highlights

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  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
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  Features an electrochemical carbon monoxide sensing technology as well as an ionization sensor that detects the fine particles of a fast-burning fire
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  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
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  Can connect to other compatible BRK or First Alert detectors, to ensure all alarms will sound when threat is detected
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  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

Main Highlights

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  Keep your family safe with this 3 pack of hardwired smoke alarms; the battery backup means constant monitoring, even if there's a power failure
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  Equipped with an ionization sensor, this smoke alarm reliably detects smoke from fast flaming fires and alerts you with an 85 decibel alarm
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  To ensure complete protection make sure to place one on each level of your home and in each bedroom
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  Can connect to other compatible BRK or First Alert smoke detectors, to ensure all alarms will sound when smoke is detected
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  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
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  Rigorously tested to meet UL standards
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  Faster turnarounds on job sites with the easy to install, most trusted alarms in home safety
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  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)

Main Highlights

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  [Hardwired interconnection] Up to 12 smoke alarms can be interconnected to cover your entire home. When one detects smoke, they all make a sound to alert everyone in the house, creating an interconnected safety net for your home.
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  [9V Battery backup] Hardwired smoke detectors are equipped with 9V lithium batteries. Ensure that all units are always connected and continue to function properly, even in the event of a power failure. Low battery alarm reminds you to replace the battery as soon as possible. If an error occurs, the system automatically triggers the fault mode, prompting you to check the device.
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  [Test Mute button and LED light] It is connected with other alarms. Just press the test/mute button on one of the units to test or mute the entire interconnected system. If the smoke alarm is in normal working condition, the green LED light is always on and the red LED light flashes every 32 seconds
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  [Photoelectric smoke sensor] Based on advanced photoelectric technology, smoke alarms can be more sensitive, fast, accurate measurement of smoke levels. More than 85 decibels of alarm sound, you can more clearly hear the danger coming.
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  [Simple installation] The installation of smoke alarm is very simple. The AC connector is connected only to the mains power and signal cables. (Please connect as instructed)

Main Highlights

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  Imported
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  Tamper resistant locking pins, single button silence test and loud 85dB alarm
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  120-Volt AC power with 9-Volt battery backup (included) to keep alarm functioning during power outage

Main Highlights

• 
  [Hardwired interconnection] Up to 12 smoke alarms can be interconnected to cover your entire home. When one detects smoke, they all make a sound to alert everyone in the house, creating an interconnected safety net for your home.
• 
  [9V Battery backup] Hardwired smoke detectors are equipped with 9V lithium batteries. Ensure that all units are always connected and continue to function properly, even in the event of a power failure. Low battery alarm reminds you to replace the battery as soon as possible. If an error occurs, the system automatically triggers the fault mode, prompting you to check the device.
• 
  [Test Mute button and LED light] It is connected with other alarms. Just press the test/mute button on one of the units to test or mute the entire interconnected system. If the smoke alarm is in normal working condition, the green LED light is always on and the red LED light flashes every 32 seconds
• 
  [Photoelectric smoke sensor] Based on advanced photoelectric technology, smoke alarms can be more sensitive, fast, accurate measurement of smoke levels. More than 85 decibels of alarm sound, you can more clearly hear the danger coming.
• 
  [Simple installation] The installation of smoke alarm is very simple. The AC connector is connected only to the mains power and signal cables. (Please connect as instructed)

Main Highlights

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  Note: A loose neutral (white wire) connection within the home junction box could prompt a device malfunction
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  Equipped with an ionization sensor, this smoke alarm reliably detects smoke from fast flaming fires and alerts you with an 85 decibel alarm
• 
  To ensure complete protection make sure to place one on each level of your home and in each bedroom
• 
  Can connect to other compatible BRK or First Alert smoke detectors, to ensure all alarms will sound when smoke 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
• 
  Rigorously tested to meet UL standards. Emits T3 pattern
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  Keep your family safe with this 6 pack of hardwired smoke alarms; the battery backup means constant monitoring, even if there's a power failure
• 
  Faster turnarounds on job sites with the easy-to-install, most-trusted alarms in home safety. easy-to-access battery drawer that allows you to replace the battery without dismounting the alarm
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  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)

Main Highlights

Main Highlights