"Inspected by US Postal Inspection Service"

This is what happens when you try to put the door in too quickly and it goes to the side. I don't care what happens, after that I'm just not in the mood to put the door in anymore

Very carefully

It is easy to bend a door when you are really only bending the empty cardboard box to have something to post

You mean UPS. Leave the USPS out of it.