First Alert SA521CN-3ST Onelink Wireless Hardwired Smoke Alarm

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First Alert SA521CN-3ST Onelink Wireless Hardwired Smoke Alarm

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List Price: $54.88
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Item Description

    Wirelessly interconnect alarms. 120VAC hardwired wireless interconnect smoke alarm with battery backup. To expand protection to include both existing hardwired alarms and new wireless alarms, simply replace one existing hardwired alarm with Onelink, then add Onelink battery operated alarms elsewhere and when one alarm in either series alarms, all alarms will be notified. Easily link alarms together with the press of a button. When one alarm sounds, they all sound for maximum whole home protection. Photoelectric smoke sensor reduces nuisance alarms from cooking smoke or shower steam. Easy access battery drawer: no need to remove alarm from ceiling to change battery. 10-year limited warranty. Meets UL standards.
    120v ac hardwired, easily replace one existing hardwired alarm with Onelink SA521 and then add Onelink battery operated alarms to connect wireless alarms with hardwired alarms--when one sounds, they all sound
  • Battery backup, provides consistent protection for added safety during power outages
  • Photoelectric smoke sensing, optimal protection from smoldering fires
  • Reduces false alarms like those caused by cooking fires and shower steam
  • Mute button, mutes unnecessary alarms immediately. also tests alarm function with same button
  • Eco-friendly, completely recyclable as an electronic device
  • EZ access battery door, no need to remove alarm from ceiling to change battery
  • Optional theft-prevention lock, when activated, batteries and/or alarm cannot be removed without proper tools
  • 2AA batteries included
  • Loud 85db alarm
  • 10-year limited warranty
  • Smoke alarms should be replaced every 10 years for maximum protection
  • Meets UL217 standard
  • FCC compliant.

From the Manufacturer


Multi Pack Indicator: No
Model No.: SA521CN-3ST
Shipping Weight (in pounds): 0.93
Product in Inches (L x W x H): 5.0 x 2.0 x 5.0
Walmart No.: 001182558

Customer Product Reviews

Rated 4.5 out of 5★ by 4reviewers.
Rated 5 out of 5★ by Being prepared for an unwanted fire... Being prepared for an unwanted fire is what these devices do. Being in one room sleeping and not hearing a smoke alarm in another room is what could happen. The Con: If other people in near by residents owning similar devices have these alarms that would affect the alarms in your resident. The device does have the ability to by pass the wireless mode and be wired together using the same fuse circuit. That would be a hassle to do, it does have that capability. 01/19/2013
Rated 4 out of 5★ by With better instuctions it would be excellent A very practical way to protect rooms that were not wired into an already built-in smoke alarm system.Worked very well. Instructions need improvement.On testing the units all seem to have a slightly different sound producing a symphony of alerts. 02/19/2009
Rated 5 out of 5★ by great alternative to hard wiring Excellent for extending existing smoke system. Easy programming. 06/15/2013
Rated 4 out of 5★ by Very easy installation Awesome 09/03/2014
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Product Warranty and Service Plan Options

Product warranty: 10 Years See details

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