Jeising GS506 Set of 3 smoke detectors / fire alarms / 10 year battery VdS certified EN14604 incl. 3 x magnetic mounting Magnetopad (tool)
This detectors are quick and easy to create a montage and also depend, if it should be necessary times. Ok, you should quite often test the part, which hopefully will not affect the battery life excessively negative. But this I find out in 8-10 years