First Alert SMI100-AC, Hardwire Interconnect Smoke Alarm with Battery Backup, 1-Pack
- First Alert's Precision Detection advanced sensing technology complies with new industry standards to reduce cooking nuisance alarms and pro…
- Through early warning interconnect, when one alarm sounds, all compatible alarms will sound
- Battery backup provides continuous protection during power outages
- Alarm indicator visually identifies the unit that initiated the alarm
- Quick Connect Plug included allows for easy installation with no need to rewire
Price & Buy Timing
Currently $19.49 — $2.80 below the 90-day average of $22.30.
All-time low: $16.20 on Tue Sep 30 (from 182 price checks).
Mubboo Value Score: 6.5/10
How it stacks up
Rated 4.6/5 — better than 78% of 37 Smoke Detectors we track. Budget-tier pricing at $19.49.
Head-to-Head vs Category Leader
| First Alert | Kidde (Leader) | |
|---|---|---|
| Price | $19.49 | $49.97 |
| Rating | 4.6/5 | 4.9/5 |
| Reviews | 2,162 | 18 |
| Mubboo Score | 6.5/10 | 5.3/10 |
The First Alert SMI100-AC, Hardwire Interconnect Smoke A is 61% cheaper but rated lower (4.6 vs 4.9).
Quick Specs
- Alarm
- Smoke Alarm
- Color
- White
- Style
- Precision Detection
- Unit Count
- 1.0 Count
- Item Weight
- 0.6 Pounds
- Sensor Type
- Ionization
- Manufacturer
- Resideo
- Model Number
- SMI100-AC
What reviewers say
Synthesized from 40 reviews · 100% verified purchases.
Test units upon arrival, as included batteries may be dead or drain quickly. Verify activation tab functions and note that sealed-battery models may not interconnect with other alarms.
Rating reliability
About First Alert
- 100 products in our database
- Average rating: 4.6/5 across all products
- Price range: $13.98 – $648
- Categories: Carbon Monoxide Detectors, Fire Extinguishers, Smoke Detectors
Other Smoke Detectors
Frequently Asked Questions
Is the First Alert First Alert SMI100-AC, Hardwire Interconnect Smoke Alarm w worth buying in 2026?
It earns a Mubboo Score of 6.5/10, with a 4.6/5 rating from 2,162 reviews — better than 78% of Smoke Detectors we track.
How much does the First Alert First Alert SMI100-AC, Hardwire Intercon cost?
It is currently $19.49. The 90-day average is $22.30 and the all-time low we recorded is $16.20.
How does it compare to the top-rated Smoke Detectors?
The First Alert SMI100-AC, Hardwire Interconnect Smoke A is 61% cheaper but rated lower (4.6 vs 4.9).
Sources & References
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