Smoke Detector Alarm (Optical Sensors)

Pros: Very cheap, has a test button and runs on a 9V battery. It also has a led to indicate its working and if the battery is low.

Cons: Tried testing it with a burning paper but it did not trigger. Maybe there wasnt enough smoke.

Other: Very cheap smoke detector!

Pros: very cheap device, easy to use, great for installing in every room. Runs on a 9V battery (included it the package), has a led to indicate its working and if the battery is low.

Cons: I can't be sure that it's working - I tried testing it with a burning shredded paper but it did not trigger. Maybe I need to burn the room for testing :)

Other: Is there other way to check if it's working? I don't really know... Not sure I can trust it to save my life in a case of fire.
It looks like a smoke detector, but I'm not sure it's doing the job.

Pros: Easy mounting Screws included for mounting 9v Battery included High sound alarm

Cons: Cheap plastic, easy to damage when mounting

Other: I would definitly buy it again if im in need. For now i have installed 2 of this model and both are tested and works perfect