Bests & Worsts Reviews from Amazon

I bought six of these. They come with everything you need to install them: base, screws, and drywall anchors. I chose not to use the anchors since there should never be significant load on the screws and screwed them straight into the ceiling. Be careful not to continue twisting after the screw head is flat or you’ll chew up the drywall and need those anchors. Anyway, easy install with just a Phillips screwdriver (standard #2). The unit fits into the base easily and has a healthy click when the unit is properly snapped in place. Also the red light blinks so you know it’s activated. Pushed the test button on each one to have my eardrums curse me, but I know they all work. Thankfully I have not had to learn whether they detect smoke efficiently. I hope I never find out.