First Alert SMI100-AC front view, offering early warning for home safety.
First Alert SMI100-AC interconnect indicator view, ensures multiple alarms chirp together.
First Alert SMI100-AC back panel with battery backup, for reliable power during outages.

First Alert

First Alert SMI100-AC Hardwire Interconnect Smoke Alarm with Battery Backup - 3-Pack

High-performance tools and home improvement made for confident daily results

$75.61

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Why customers choose TaskHolt Tools

Overview

Meet the First Alert SMI100-AC, a hardwire interconnect smoke alarm designed for simple upgrades and reliable protection. With a 3-pack, you can create a cohesive early warning network across rooms and levels, helping you stay informed as situations evolve.

Smart sensing for real-life safety

First Alert’s Precision Detection advances smart sensing to differentiate common cooking smoke from genuine fire risk, reducing nuisance alerts while still providing timely warnings when danger appears.

Interconnect capability means that when one unit detects smoke, all compatible alarms in the network sound together, helping you wake and respond quickly.

  • Precision Detection aligns with newer standards to balance safety and minimize false alarms
  • Interconnect across First Alert alarms for synchronized alerts
  • Battery backup maintains protection during power outages

Easy installation and daily use

The Quick Connect Plug simplifies wiring and installation, letting you replace existing alarms with no rewiring. The unit also features a visual indicator to identify which alarm triggered the alert.

  • Quick Connect Plug for fast setup
  • Visual alarm indicator pinpoints the initiating unit
  • Interconnect compatibility with other First Alert devices for a full-home system

Practical benefits you can count on

In residential settings, this 3-pack supports coverage in living spaces, hallways, and bedrooms. Battery backup maintains protection during outages, while clear audible alarms help you respond calmly and decisively.

FAQ

Q: What is the First Alert SMI100-AC and how does it work?

A: The SMI100-AC is a hardwire interconnect smoke alarm with battery backup that provides early warning and connects with compatible units to form a whole-home system.

Q: How easy is installation and can I replace my existing alarms easily?

A: Yes. The Quick Connect Plug simplifies wiring and no rewiring is needed to install or replace existing alarms, and interconnects help audible alerts travel through the home.

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