My box is 2 1/4 deep the divided tray has 13 11/2 X 11/2 compartments and one that is 1 1/2 X 3. The second tray is open and I glued some two pieces of magnetic sign material in it. That holds my bigger streamers and wet, moist, flies. Which allows the flies to dry with squishing the hackle.
I also have a small plastic lined tobacco pouch Velcroed to the front that hold my tippet material. I have never been bothered by this set up.