Gluman Dinner Set with 32 Pieces, 6 People Ideal for gift-giving and easy to clean. Made of virgin polypropylene, this container can be used for both reheating and serving directly from the refrigerator to the microwave. Wash with liquid detergent and a sponge for the best results. In an oven or stove, the product shouldn't be heated up directly. Products can only be reheated in the microwave for three minutes.