1. Skin-friendly, Environmentally friendly material. The carefully polished mugs are more comfortable.
2. In order to activate funny coffee mugs the temperature of the hot liquid should be over 70 degree C. At that temperature it is possible for the color of the coffee mug to change. 3. Makes your morning more fun: Beat the sadness that the morning brings with this exciting Color Changing Mug. As it changes and you can watch the Battery fully charge. 4. Great mug gift in a special day for someone. Good for birthday, Farther Day, Mother Day, Valentine Day, Teacher days, Christmas, Thanksgiving, etc 5. Wash with hand or a mild detergent and a soft cloth or sponge. Get away from dishwasher and microwave oven.