You can tell that the box has been used, and it is the cheap kind of cardboard. I have sent many things all sizes and shapes and weights across the world. And so far not one problem. If I send a heavy item I pack it well and in a box that is two layers of cardboard, it is made that way. Do not expect the USPS to pack boxes for you or tell you that it won't hold up. I work in a USPS processing plant and I can tell you we do care about your mail but with thousands of packages passing through daily they must move fast. How many times has your baggage been damaged on the airlines...same thing. Pack it well and you will have no problems.