This is a great storage solution!  I have melasma so I wear hats outside constantly.  Since my collection keeps growing, I decided to test this product out.  You are given 2 belts that hold 9 hats each with 2 different ways of attaching the belt to the door.  I choose the less permanent version which took all of 2 minutes to install.  Easy peasy and works like a charm!

A reviewer said the belts weren't long enough for their door, but mine was fine with room to tighten.  These 100% for sure fit a standard sized door.
I liked it so much I ordered another set the next day..ha!  I now have 3 rows on my bedroom door and I'm saving the extra belt in case I need it later!