At 6 feet deep by 6 feet wide, this size unit is just deep enough to store a full size mattress (without being on an angle). But you can store a lot of other large pieces in it.

This is our most popular size. At 7 feet, this unit is deep enough to store a queen or king size mattress, box spring, head and foot board and lots of other stuff. May be a little tight for a California king size mattress if you have a lot of other stuff.

Will easily hold a king size mattress, box spring, head and foot board with room to spare.

At 10 feet deep you can store very long items here including a California king size mattress and head/footboard.