Description: I made this cage rack from 3/4" red oak plywood. Cages are supported by 2 pine 2x4's into which I cut recesses for a flush-fitting piece of 12"x24"x3/4" styrofoam exterior house insulation. I then sandwiched a 24"x11" piece of mylar heat tape between cage bottoms and insulation for more efficient cage heating. I ran all three cages off of one Biostat AT thermostat. I also mounted 60 watt bulbs over each right side vent and ran bulbs on a timer. Nothing is attached to cages so they slide in and out for easy maintenance. All cords and controls are hidden from view, plus there's no place for a naughty hottie to hide under the rack. I placed a pad lock through each plexiglass front for added security.