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BRK SC9120B Smoke & Carbon Monoxide Detector

4.8324 product ratings
Hollar Exchange (606)
99.4% positive feedback
Price:
$44.99
Returns:
30 days returns. Seller pays for return shipping.
Condition:
New
See pics for details.

About this product

Product Identifiers

BrandBRK
MPNSC9120B
UPC0029054513069
ModelSC9120B
eBay Product ID (ePID)1029452962

Product Key Features

Power SourceHardwired
ColorWhite
Item Depth2.35 in
FeaturesBattery Backup
TypeSmoke & Carbon Monoxide Detector

Dimensions

Item Width5.76 in
Item Diameter5.6 in
Item Weight0.72 lb

All listings for this product

Buy It Nowselected
New
First Alert SC9120B Combined Carbon Monoxide & Smoke Alarm AC Power Battery NEW
item 1 First Alert SC9120B Combined Carbon Monoxide & Smoke Alarm AC Power Battery NEW
$44.99
First Alert SC9120B Combined Carbon Monoxide & Smoke Alarm AC Power Battery
item 2 First Alert SC9120B Combined Carbon Monoxide & Smoke Alarm AC Power Battery
$49.99
Free shipping
NEW BRK SC9120B Smoke & Carbon Monoxide Detector
item 3 NEW BRK SC9120B Smoke & Carbon Monoxide Detector
$52.00
+$0.90 shipping
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Almost gone
item 4 NEW BRK SC9120B Smoke & Carbon Monoxide Detector First Alert
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First Alert SC9120B/SMICO100 Combination Carbon Monoxide & Smoke Alarm AC Power
item 5 First Alert SC9120B/SMICO100 Combination Carbon Monoxide & Smoke Alarm AC Power
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item 6 First Alert Carbon Monoxide & Smoke Alarm AC Power + battery NIB
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BRK Smoke/CO Alarm,2 in H,5.6 in W 825LZ1
item 9 BRK Smoke/CO Alarm,2 in H,5.6 in W 825LZ1
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item 10 BRK SC9120B 120V AC/DC Smoke/CO Combo Alarm
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BRK SC9120B Smoke & Carbon Monoxide Detector
item 11 BRK SC9120B Smoke & Carbon Monoxide Detector
$29.99
BRK SC9120B Smoke & Carbon Monoxide Detector
item 12 BRK SC9120B Smoke & Carbon Monoxide Detector
$39.40
BRK SC9120B Smoke & Carbon Monoxide Detector
item 13 BRK SC9120B Smoke & Carbon Monoxide Detector
$45.00
BRK SC9120B Smoke & Carbon Monoxide Detector
item 14 BRK SC9120B Smoke & Carbon Monoxide Detector
$47.00
New BRK Professional Standard SC9120B Smoke & Carbon Monoxide Detector AC Power
item 15 New BRK Professional Standard SC9120B Smoke & Carbon Monoxide Detector AC Power
$49.99
First Alert SC9120B Combined Carbon Monoxide & Smoke Alarm AC Power, Battery
item 16 First Alert SC9120B Combined Carbon Monoxide & Smoke Alarm AC Power, Battery
$50.00
BRK SC9120B Smoke & Carbon Monoxide Detector
item 17 BRK SC9120B Smoke & Carbon Monoxide Detector
$54.00
BRK SC9120FF Hardwired Smoke & Carbon Monoxide Detector with Battery...
item 18 BRK SC9120FF Hardwired Smoke & Carbon Monoxide Detector with Battery...
$59.00
BRK SC9120B Smoke & Carbon Monoxide Detector Hardwire With Battery Backup New
item 19 BRK SC9120B Smoke & Carbon Monoxide Detector Hardwire With Battery Backup New
$168.99
listings for this product

Ratings and Reviews

Learn more
4.8
24 product ratings
  • 21 users rated this 5 out of 5 stars
  • 2 users rated this 4 out of 5 stars
  • 1 users rated this 3 out of 5 stars
  • 0 users rated this 2 out of 5 stars
  • 0 users rated this 1 out of 5 stars

Would recommend

Good value

Good quality

Most relevant reviews

See all 24 reviews
  • by ricprims0
    Aug 02, 2025Top favorable review

    SC9120B smoke and carbon detector.

    Could not find the smoke detector anymore, it has been replaced with another model. eBay saved me from having to replace 5 other of the same detector. Works perfectly.

    Verified purchase: YesCondition: New

  • by 383powered
    Apr 03, 2024Top critical review

    Poor business!

    Just can’t understand how anyone can produce anything that is programmed to fail at a certain time interval. Would you purchase a tv that only lasts five years?? How about an automobile the would be programmed to leave you along side of the road after a certain time frame?? Why do we accept this for this manufacturer?

    Verified purchase: YesCondition: New

  • by avar1460
    May 15, 2025

    Good purchase.

    Everything appears to be new and is in great shape, no damage. I would have preferred them to be in original boxes but I knew they weren't when I purchased them. Have only used one so far and is working great.

    Verified purchase: YesCondition: New

  • by bezerker77
    May 15, 2025

    Brand new with working battery ... thank...

    Brand new with working battery ... thank you!!

    Verified purchase: YesCondition: New

  • by snhuin
    Jun 08, 2024

    Item works as it should. Excellent!

    Item works as it should. Excellent!

    Verified purchase: YesCondition: New

  • by imsowow
    Jan 09, 2025

    Awesome. Brand new! Thank you! ...

    Awesome. Brand new! Thank you!

    Verified purchase: YesCondition: New

  • by rrsw_s_00prctz
    Jul 27, 2024

    exact replacemnt for ones being retired.

    What can you say, its a co2/smoke alarm. It is the exact same model of the one it replaces which is eight years. The new one is mfr'd in2024 which is what I needed.

    Verified purchase: YesCondition: New

  • by kimgdlp
    Apr 17, 2024

    Item as described. Used to replace end of life unit.

    Item as described. Used to replace end of life unit.

    Verified purchase: YesCondition: New

  • by willicolo-6
    May 29, 2024

    i have bought 3 in the past 2 years and ...

    i have bought 3 in the past 2 years and with this one 4 its a great product.

    Verified purchase: YesCondition: New

  • by marcjohnson2000
    May 01, 2024

    Fantastic carbon monoxide detector. The item works as expected.

    Fantastic carbon monoxide detector. The item works as expected.

    Verified purchase: YesCondition: New

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