The Print Pad is a method for shipping unframed pieces flat for artwork that is better preserved not rolled or simply cannot be rolled to keep its integrity intact.  The Print Pad is constructed of a long scored pad, four corners, and a sleeve.  All you do is center your print, photograph, etc. in the middle of the upper layer of the long scored piece of double wall corrugated and fold the corners to fit around your piece.
It is also available with the ABS Plastic liner lined to the inside top and bottom just as the Strongbox. 
While considerably more expensive in the Print Pad, is provides uncompromised strength to keep it from bending.