The boxes are used to store prior year tax returns. These boxes weigh too much when full. They are too long and not easy to handle because of their length.
I have a HUGE personal research library and have moved several times over the past five years. I couldn't be without these book boxes. They pack travel and store very well and I couldn't live without them.
Only downfall is that if you fill up these boxes (like I do) the tops will cave in under the weight of the files. Also once you have them full don't try to move them much otherwise they will crumble apart on you. Recommend only filling them about 1/2 way then they work great!
We use these boxes for long term storage of old files. They are economical and very adequate for this purpose. I stack them three high and have never had a problem with them.