I bought 4 of these about 2 weeks ago to install in the ceiling for my home theater for the .4 in a 7.2.4 home theater build. It took me a while to figure out how the plunger screw thing worked - I thought I was doing something wrong. But you have to turn left, then right and plunger will easily tighten down. I didn't know this and was applying the force of superman to crank down the plunger. After about the 3rd install I realized the trick. 2 were installed in a drop ceiling and the other 2 where installed in a drywall ceiling. Templates provided made for easy cutting of holes. The sound from them is just simply amazing and work really well with the rest of my NHT setup. I was amazed at how big they are. I'll post some pictures shortly of the install - but here are some of the speaker itself.