Tiffin is an old-fashioned English word for a light lunch, and sometimes for the box it is carried in. Each compartment holds a different type of food that can be later mixed together helping food to stay fresh and not soggy. Instructables website shared how you can make it yourself with aluminum tuna cans.
Click here:
http://www.instructables.com/id/Tiffin-Box-from-Tuna-Cans/