Nest Protect Smoke + CO Alarm review
Test score %

The Nest Protect Smoke + CO Alarm can send alerts about dangerous levels of carbon monoxide or smoke direct to your smartphone, which is a handy touch if you’re out of the house at the time. This more advanced two-in-one functionality, along with its 10-year lifespan, pushes the price up far above the price of a standard CO alarm – but is it an investment worth making? We put the Nest Protect Smoke + CO Alarm through a series of stringent carbon monoxide safety detection tests to find out.
- Pros and cons

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