All of the self locking trays on the market today require extra board to be as strong as a taped or stapled tray. The Perma-Lock Tray by IDCI is a self locking tray that is as strong as a stitched or taped tray and is the SAME SIZE Blank! And the Perma-Lock Tray cannot open when the Perma-Lock is engaged and the tray filled with your product. The Perma-Lock design also allows you to have a shape that conforms to your product. You can have a square, rectangle, or even an eight sided tray.