A quality detector, a service that goes to the stack of paper and end notification

I replaced two conventional low-cost detectors operating with a 9V battery by these detectors that appeared to be of a higher quality level. I chose this model because of the presence of a lithium battery. The calculation is quickly done by counting the annual replacement of old 9V batteries with respect to the lifetime of the lithium battery of 5 years ...

I am not disappointed:
- The build quality seems to be at the rendezvous Exterior.
- I enjoyed the online registration to prevent us from near the end of battery (theoretical time = 5 years) and the end of life of the detector, and manage warranty.
- They are compact and very easy to install. A screw enough.
- The noise level is very powerful.
- The power indicator light is very discreet and does not bother children (these detectors are installed in their rooms, we have other sensors in the hallways)

I recommend this product without reservation.
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