BRK SC9120B Smoke and Carbon Monoxide Alarm
Price as of 2026-06-02. Check Amazon for the current price.
Quick Decision
Price Intelligence
- Budget:$17–$39
- Mid-range:$39–$93← You are here
- Premium:$93+
Is This Right For You?
- •Those who want a top-rated option — in the top 5% of Smoke Detectors by rating
- •First Alert Smoke Alarm — 53% cheaper at $24 (Score A)
📊 Based on data analysis of 37 products in this category.
Mubboo Score: B
How we calculate the Mubboo Score
Quality (45%): customer rating, normalized to a 10-point scale
Popularity (35%): review volume vs the category leader, log-scaled
Value (20%): price position vs other Smoke Detectors
Computed from live Amazon rating, review count, and price across 37 Smoke Detectors available to US consumers · last refreshed 2026-06-02.
How It Compares
This Product BRK SC9120B Smoke and Carbon Monoxide Alarm | Most Popular First Alert Smoke Alarm | Best Rated Kidde AC Hardwired Interconnect Smoke Detector Alarm | Best Value Kidde Smoke Detector | |
|---|---|---|---|---|
| Price | $52.44 | $24.47 | $39.99 | $29.21 |
| Rating | 4.7/5 | 4.4/5 | 4.6/5 | 4.1/5 |
| Reviews | 270 | 8,237 | 814 | 2,033 |
| Mubboo Score | B | A | B+ | B+ |
Quick Specs
- Item Weight
- 10 ounces
- Part Number
- SC9120B
- Manufacturer
- BRK
- Power Source
- battery-powered
- Customer Reviews
- 4.6 out of 5 stars
- Battery Cell Type
- Alkaline
- Item model number
- SC9120B
- Package Dimensions
- 5.79 x 5.75 x 2.4 inches
What People 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.
- Ease of Installation
- Good Value
- Reliable Performance / No False Alarms
- Compatibility with Existing Mounts
- Long Battery Life / No Battery Changes
- Pre-installed Battery Drains Quickly
- Dead on Arrival / Activation Issues
- Flimsy Build Quality
- Confusing Instructions
Expert Picks in Smoke Detectors
- Kidde Smart Smoke Detector — Best smoke detector overall
- First Alert Battery Smart Smoke & Carbon Monoxide Alarm with Nest Protect — Best for Google Nest users
- Kidde Ring-Enabled Smart Smoke and Carbon Monoxide Detector — Best smoke detector for Alexa and Ring users
- First Alert SMI100 Dual Sensor Smoke Detector — Best budget smoke detector
Category recommendations from independent expert publications. Source links in References.
Related Video Reviews
- 📹 What Most Homeowners Don’t Know About Carbon Monoxide Detectors — The DIY HVAC Guy
- 📹 Best Carbon Monoxide Detectors in 2026 — wiredtech
- 📹 7 Best Carbon Monoxide Detector 2026! Tested & Tried — Everything Under Control
Key Features
- ✦Superior carbon monoxide sensor and dual ionization smoke alarm
- ✦Simple to use silence/test button; separate smoke and CO latching alarm indicators
- ✦9-volt battery included; 7-year limited warranty
- ✦Inter-connectable with BRK and First Alert hardwired smoke and carbon monoxide alarms
- ✦Easy to install universal mount bracket
Source: product listing on Amazon.
About BRK
- 13 products in our database
- Average rating: 4.8/5 across all products
- Price range: $18.99 – $233.98
- Categories: Carbon Monoxide Detectors, Smoke Detectors
If not the SC9120B Smoke and Carbon Monoxide Alarm, consider these
Bottom Line
BRK SC9120B Smoke and Carbon Monoxide Alarm earns Mubboo Score B. Priced at $52 — a mid-range option, below the category average of $77. Rated 4.7/5 from 270+ reviews. Strong buy if: those who want a top-rated option.
Frequently Asked Questions
Is the BRK SC9120B Smoke and Carbon Monoxide Alarm worth buying in 2026?
It earns a Mubboo Score of B, with a 4.7/5 rating from 270 reviews — better than 95% of Smoke Detectors we track.
How much does the BRK SC9120B Smoke and Carbon Monoxide Alarm cost?
It is currently $52.44 — mid-tier pricing for Smoke Detectors.
How does the SC9120B Smoke and Carbon Monoxide Alarm compare to other Smoke Detectors?
The category's most-reviewed alternative is the First Alert Smoke Alarm (4.4/5, 8,237 reviews, $24.47). The SC9120B Smoke and Carbon Monoxide Alarm carries a Mubboo Score of B vs A.
Sources & References
Products available through US retailers. Prices in USD. Sales tax varies by state and is not included.
Mubboo may earn a commission on purchases made through affiliate links. This does not affect our Mubboo Score, product rankings, or editorial judgments. Prices are accurate as of the last sync (2026-06-02) and may change.