What should I put in my case to replace the unused tray for a floppy drive (or ssd)

computersarecool

Honorable
Dec 27, 2013
9
0
10,510
I just bought a case. I really like it except that it has a bunch of slots for CD Rom drives or floppy disk drives or something. Since I am not using those, but they were made to come out, just a light tap will push the tray cover back into the computer. What should I put there to permanently fill the gap?