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First Alert SMI100-AC Hardwired Ionization Smoke Alarm with 9V Backup, 12-Pack - product image 1
First Alert SMI100-AC Hardwired Ionization Smoke Alarm with 9V Backup, 12-Pack - product image 2
First Alert SMI100-AC Hardwired Ionization Smoke Alarm with 9V Backup, 12-Pack - product image 3
First Alert SMI100-AC Hardwired Ionization Smoke Alarm with 9V Backup, 12-Pack - product image 4
First Alert SMI100-AC Hardwired Ionization Smoke Alarm with 9V Backup, 12-Pack - product image 5
First Alert SMI100-AC Hardwired Ionization Smoke Alarm with 9V Backup, 12-Pack - product image 6
First Alert SMI100-AC Hardwired Ionization Smoke Alarm with 9V Backup, 12-Pack - product image 1
First Alert SMI100-AC Hardwired Ionization Smoke Alarm with 9V Backup, 12-Pack - product image 2
First Alert SMI100-AC Hardwired Ionization Smoke Alarm with 9V Backup, 12-Pack - product image 3
First Alert SMI100-AC Hardwired Ionization Smoke Alarm with 9V Backup, 12-Pack - product image 4
First Alert SMI100-AC Hardwired Ionization Smoke Alarm with 9V Backup, 12-Pack - product image 5
First Alert SMI100-AC Hardwired Ionization Smoke Alarm with 9V Backup, 12-Pack - product image 6

Disclaimer: Actual product colors may vary slightly from the images shown due to different monitor settings and lighting conditions during photo shoots.

First Alert

First Alert SMI100-AC Hardwired Ionization Smoke Alarm with 9V Backup, 12-Pack

Out of stock
SKU: SMI100-AC 12 PACK NEW
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$173.12
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Overview

The First Alert SMI100-AC is a hardwired smoke alarm with a replaceable 9V alkaline backup battery, supplied here as a factory 12-pack. Its ionization smoke sensor and Precision Detection technology are designed for compatible residential 120 V AC alarm systems.

Key Features

  • Detection: Ionization smoke sensing with First Alert Precision Detection technology.
  • Backup protection: One replaceable 9V alkaline battery keeps the alarm operating during a power outage.
  • Interconnection: Compatible hardwired First Alert or BRK alarms sound together when one unit detects smoke.
  • Installation: The included Quick Connect plug simplifies compatible replacements without rewiring.
  • Audible warning: 85 dB alarm at 10 ft, plus low-battery and end-of-life warnings.

Specifications

  • Model: SMI100-AC
  • Brand: First Alert
  • Type: Smoke Alarm
  • Sensor Type: Ionization (smoke)
  • Power Source: AC-powered
  • Connectivity: Wired
  • Operation Mode: Interconnected
  • Operating Voltage: 120 V AC, 60 Hz
  • Battery Backup: Yes
  • Backup Battery Type: 1 × 9V alkaline
  • Hardwired Interconnectivity: Yes; compatible First Alert/BRK hardwired alarms
  • Sound Level: 85 dB at 10 ft (3 m)
  • Mounting Type: Ceiling or wall
  • Operating Temperature: 40°F to 100°F (4°C to 38°C)
  • Certifications: UL Listed; UL 217

Common Applications

  • Multi-room residential smoke-alarm replacements requiring a coordinated 12-unit installation.
  • New or existing compatible hardwired alarm systems with battery backup.
  • Homes where interconnected alarms provide an earlier warning across multiple rooms.

Free shipping on eligible orders over $90. Our shipping cutoff is 3 PM, Monday–Friday. Available shipping services and delivery estimates are shown at checkout.

See our shipping policy for eligibility and exclusions. Orders are delivered; our warehouse is closed to the public.

Your product is covered by a 12 month Warranty or more if you opted for the extended warranty. Make sure you register your product.

Product Specifications

  • Brand First Alert
  • Model SMI100-AC
  • Power source AC-powered
  • Mounting Type Ceiling or wall
  • Certifications UL Listed and UL 217
  • Product Height 1.9 in
  • Product Width 5.6 in
  • Product Length 5.6 in
  • Product Weight 0.6 lb
  • Connectivity technology Wired
  • Detector operation mode Interconnected