Unbranded Carbon monoxide alarm 4 review
Product alert
Don't Buy this carbon monoxide (CO) alarm – it failed to sound in 17 of our carbon monoxide detection tests
It failed to detect CO in 17 of our detection tests and it can't be trusted to alert you if there’s a build-up of the deadly gas in your home.
Further reading
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Test resultShow Context

This dangerous carbon monoxide (CO) alarm cannot be relied upon to detect CO and then sound the alarm when you need it to. That's why we’re making it a Don’t Buy. It failed to detect CO in 17 of our detection tests and can't be trusted to alert you if there’s a build-up of the deadly gas in your home. If you have this alarm, you should replace it as soon as possible with a model from a well-known brand.
What's included:- Pros and cons
First reviewed by Which?
October 2019
Released
January 2019

Technical specifications
The overall Which? test score is made up of the following star ratings, all determined by our rigorous lab tests.
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