These rubber bands are great for securing the contents of overstuffed file folders. They're hard to find but I finally found them at Staples (on the bottom shelf).
My wife uses them to secure plastic food trays which can sometimes pop open on the way home from the market. One package of these rubber bands can last a long time!
These colorful rubber bands hold together a set of my work files. I’d say they’re about 6 inches plus deep. I can’t afford to have the sensitive information get out of their file folders!