Foldtuk Kitchenware 4-cup Red Square . You can now choose to make your dishes in the shape that most appeals to you. Some foods just look better square-shaped You can easily put together a tray of lasagna a casserole or even a layered cake in the square FoldTuk. You may even find that FoldTuk cooks faster and more thoroughly than most other cookware or bakeware products Made of silicone and ceramber thats a silicone and ceramic blend they can be used in both a microwave and regular oven