It's a remix of cruzher's work so you can have a drawer that's slightly more than twice the height of the current drawers without modifying the shelf. It's useful for small parts that don't fit with the height of a single drawer. =)
If you want to modify it, use the file Double_Drawer_base.123dx, this is basically where you can start from to make other type of drawers (i.e. with more compartments).
See the my page at Thingiverse for instructions on how to print it.
See Thingiverse for the crusher's Small items organizer.