Plastic is torn based on long term storage.  Please see pictures. Some warping to the box it feels like but no hindrance to it's use.

This Springbok 1000 piece jigsaw puzzle features a colorful and delightful theme of cats and comes in a sealed package. It is made of sturdy cardboard material with interlocking pieces and measures 24"x30". The puzzle is designed to provide a complete and satisfying experience to the puzzler. It is manufactured in the United States and is perfect for anyone who enjoys puzzles.