Which is better, Google Nest Protect or First Alert BRK 3120B Hardwired Dual-Sensor?

Based on our trust score analysis, First Alert BRK 3120B Hardwired Dual-Sensor scores 9.2/10 compared to Google Nest Protect at 9.0/10. First Alert BRK 3120B Hardwired Dual-Sensor ranks higher across expert reviews, user sentiment, and value metrics, making it the stronger choice overall.

What is the price difference between Google Nest Protect and First Alert BRK 3120B Hardwired Dual-Sensor?

Google Nest Protect is priced at $109.00 – $129.00 and First Alert BRK 3120B Hardwired Dual-Sensor is priced at $30.00 – $42.00. Google Nest Protect is the more expensive option at $109.00 – $129.00, while First Alert BRK 3120B Hardwired Dual-Sensor comes in at $30.00 – $42.00.

Is Google Nest Protect worth the extra money over First Alert BRK 3120B Hardwired Dual-Sensor?

Google Nest Protect ($109.00 – $129.00) has a value score of 8.2/10 compared to First Alert BRK 3120B Hardwired Dual-Sensor ($30.00 – $42.00) at 8.5/10. First Alert BRK 3120B Hardwired Dual-Sensor offers better value for money despite the lower price point.

Home / Carbon Monoxide Detectors / Google Nest Protect vs First Alert BRK 3120B Hardwired Dual-Sensor

Google Nest Protect vs First Alert BRK 3120B Hardwired Dual-Sensor

Name: First Alert BRK 3120B Hardwired Dual-Sensor
Brand: First Alert
Rating: 4.7 (1 reviews)

Head-to-head comparison based on trust scores, features, pricing, and real user feedback.

Our pick: First Alert BRK 3120B Hardwired Dual-Sensor (Trust Score 9.2 vs 9.0)

Google Nest Protect

Google

$109.00 – $129.00

9.0

Excellent

Best Value

Pros

+Voice alerts name danger type and location
+Split-Spectrum dual sensing
+Phone notifications and remote silence
+Voice alerts with specific danger type
+Automatic self-testing

Cons

−Most expensive CO detector
−Premium price per unit
−Requires Google Home ecosystem
−No Thread or Matter support

Don't buy if

⚠ The Nest Protect has a 10-year sealed battery lifespan; it cannot be battery-replaced and the entire unit must be discarded after 10 years.
⚠ The Nest Protect cannot be silenced from older Nest apps; ensure you use the Google Home app for full functionality.

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First Alert BRK 3120B Hardwired Dual-Sensor

First Alert

$30.00 – $42.00

9.2

Excellent

Runner-Up

Pros

+Dual ionization and photoelectric sensors
+Dual ionization and photoelectric sensors
+Interconnects up to 18 units
+Interconnects up to 18 units
+Battery backup for power outages

Cons

−Requires hardwired installation
−Requires hardwired installation
−No smart/Wi-Fi features
−No smart/Wi-Fi features

Don't buy if

⚠ Hardwired installation should be done by a qualified electrician to ensure proper interconnect wiring.
⚠ Hardwired installation should be done by a qualified electrician to ensure proper interconnect wiring.

Check Price on Amazon

Score Comparison

Metric	Google Nest Protect	First Alert BRK 3120B Hardwired Dual-Sensor
Trust Score	9.0	9.2 ✓
Expert Score	8.8	9.4 ✓
User Sentiment	9.1	9.2 ✓
Value Score	8.2	8.5 ✓
Complaint Risk	8.7 ✓	8.8
Price	$109.00 – $129.00	$30.00 – $42.00

The Verdict

First Alert BRK 3120B Hardwired Dual-Sensor wins this comparison with a Trust Score of 9.2 vs 9.0. It's rated "Runner-Up" and scores higher across the majority of our evaluation criteria. However, the Google Nest Protect may be a better fit depending on your specific priorities — check the pros and cons above.

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