They are made from 1X3 fastened to the back of the tank stand. I will hang my Aqua Illumination Sols on one of the rails from their hanging kit across the two hangers.
The screws from fastening the 3/4" plywood top of the stand are not all the way below the surface of the plywood. I didn't counter sink the screws and when you rub you hand over them you can feel them. The Lee-Mar tank does have a plastic bottom the covers the whole bottom glass but I just wanted to make sure with all the weight the screws wouldn't become an issue.