First Alert SMI105-AC Interconnect Hardwire Smoke Alarm
First Alert

First Alert SMI105-AC Interconnect Hardwire Smoke Alarm

4.5

Best interconnected safety solution for modern homeowners seeking reliable protection.

This hardwired unit offers the ultimate peace of mind by linking every alarm in your home to sound in unison. While installation requires a bit more effort than a simple battery-operated model, the decade-long battery backup and intelligent nuisance reduction make it a set-it-and-forget-it essential for serious home safety.

$30.99

In stock

at

Walmart

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Detection Technology Photoelectric
Dual Sensor Ionization
Photoelectric
Power Source Hardwired with Battery Backup
Battery Operated
Hardwired with Battery Backup
Hardwired, Battery Operated
Connectivity Type Hardwired Interconnected
Hardwired Interconnected
Standalone
Interconnectivity Type Hardwired Interconnect
Hardwired Interconnect
None

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Who it's for

  • Homeowners seeking comprehensive coverage for multi-story or large residences
  • Design-conscious residents who prefer discreet safety hardware
  • Safety-focused families living in areas prone to electrical grid failures

Who should skip it

  • Renters or DIY novices looking for a simple peel-and-stick solution
  • Safety purists who prefer dual-sensor technology for all fire types
  • Homeowners installing alarms near kitchens or high-humidity bathrooms

Performance breakdown

Interconnectivity Reliability

Hardwired connection ensures every alarm sounds instantly across the entire home.

Excellent

Maintenance Convenience

Ten-year sealed battery eliminates the hassle of annual battery changes.

Excellent

Nuisance Alarm Prevention

Advanced sensing technology effectively filters out common kitchen smoke and steam.

Excellent

Emergency Clarity

Visual indicators quickly pinpoint the specific unit that triggered the alert.

Excellent

Installation Complexity

Hardwiring requires basic electrical knowledge, making it less plug-and-play.

Good

Lifecycle Management

Clear end-of-life warnings remove guesswork about when to replace the unit.

Excellent

Key Specs

Detection Technology

Photoelectric

Power Source

Hardwired with Battery Backup

Connectivity Type

Hardwired Interconnected

Interconnectivity Type

Hardwired Interconnect

Battery Type

Lithium (Sealed)

Battery Life

10 years

Alarm Sound Level

85 dB

Alert Type

Siren / Beep

Alarm Type

Siren

Hush Button Feature

Yes

Know before you buy

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First Alert SMI105-AC Interconnect Hardwire Smoke Alarm

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Walmart
Walmart
In stock
$30.99
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