Why can't you ship to PO or APO boxes?

We cannot ship to PO or APO Boxes with internet orders. There are a couple of reasons for this. One is that many of our items are large and ship in boxes bigger than the post office will accept for postal boxes. Our on-line order system can't determine what size of box your order will ship in. Another reason is that we ship items, like treadmill lubricant, that cannot be shipped through the US postal service.