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First Alert Hardwired 120V Electrochemical/Ionization Carbon Monoxide and Smoke Alarm

Marsoni M251S
Sale price$77.99
Pay 4 payments of $19.50 a month.Shop Pay
Get it in 3 business days with 1 day shipping. Friday, May 29
First Alert Hardwired 120V Electrochemical/Ionization Carbon Monoxide and Smoke AlarmElectrochemical & ionization sensor Designed for hardwired installation, but features a 10 year battery back up allowing the unit to function if the power goes out Hardwire adapter so there is no need to rewire Can be connected to other compatible BRK or First Alert CO smoke detectors within a single family residence Includes single button silence or test function 10 year limited warranty
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Exchange/Return Notes
  • We offer a 30-day return/exchange service after receiving.
  • Final sale items are not eligible for returns or exchanges.
  • To process your return/exchange, please contact us at [email protected]
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4.3 ★★★★★
Based on 281 reviews
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Product Reviews
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NY2CO
Cuba, US
★★★★★ 5
Save money by installing yourself
Size: 9.5" x 10.9" x 2.1"
Good price and easy to install in a 2019 Honda CRV. Instructions can be found on YouTube. Much less expensive than having a service center install them.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on February 14, 2026
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Verified Purchase
Customer Review
Lowell, US
★★★★★ 4
Always fits and is easy to install
Size: 9.5" x 10.9" x 2.1"
We've bought these for years and they always fit and are easy to install. Easy to see when they are dirty and need to throw away. Embarrassed that we let the car dealership do it for so long. We set on six-month subscribe and save so that we know when to replace it - change it whenever it shows up!
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Reviewed in the United States on September 13, 2023
R
Verified Purchase
Randy Shiverdecker
Whiting, US
★★★★★ 5
Better than I expected.
Size: 9.5" x 10.9" x 2.1"
Fits perfectly. Easy to install. As good of quality as the original equipment filter.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on January 9, 2026
V
Verified Purchase
Victor Escobar
Alexandria, US
★★★★★ 5
Great
Size: 9.5" x 10.9" x 2.1"
Excellent product! My car really needed it. Super fast delivery and the best price. I'm super happy with this product.
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Reviewed in the United States on November 12, 2025
G
Verified Purchase
Gladys
Charlottesville, US
★★★★★ 5
Honda crv filter
Size: 9.5" x 10.9" x 2.1"
Good cabin filter for my 2019 Honda crv
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 11, 2026

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