USPS Fail

I mailed some main caps to a shop 150 miles from me taped together and packed in some styrofoam in a flat rate box. When I heard nothing from the shop I called to see how they worked out and he told me he never got them. So, I went to USPS and filed a claim. Several weeks later I got a bag from the postal service in Minneapolis, MN. The note with the package said that my package was undeliverable because of "illegible recipient address". Well, inside the package were the four main caps tightly taped together and the remains of a box which had obviously been run over in the mud. There were clearly visible tread marks in the mud left on the smashed box. The corner with the shipping address was completely ripped off. Good thing I had attached a return address label and that portion of the box survived or I would never have seen my Pro-gram caps again!