The installation on the ceiling is quite simple with screws and dowels. The smoke detector is activated by pressing the test button. A key I have searched in vain. I twisted and turned the part to see the button. A bit of a misnomer. Ultimately, just press 5 seconds the surface of the smoke detector until an LED light will light up. After 1 second release. A loud BEEP confirms the activation. The BEEP is quite loud and clearly heard to test even with the television in the bedroom and closed the door yet.
I will get me these smoke detectors to the other rooms. A good product, unobtrusive, easy to install, easy to use, recommended.
