You can find the information you need in a couple of different ways depending on how you are using Houzz. If you are on a computer, click on the "more info" link. If you are using the app, tap on the photo. Either way there should be a link to a vendor or a store. You should be able to get further information by following that link.

Thank you for contacting Bellacor. The item can be mounted either up or down. You would have to have 3 separate junction boxes to install the items. The back plate is 4¾” square. The item would look good over the mirror. You would probably want to space the lights about 22" apart.