Pour your favorite hot beverage into the Harry Potter Magic Wand Heat Change Mug and watch as it magically transforms before your eyes. When cold, the mug is dark. However, as soon as the mug is warm the wands of Harry, Hermione, and Ron spark into action firing bolts of magic, illuminating the Harry Potter logo. This Harry Potter Magic Wand Heat Change Mug is the perfect gift for lovers of the Harry Potter books and movies. Makes a great accompaniment to your next tea-break. The Harry Potter Magic Wand Heat Change Mug is great for use at home, at work, or at school. Hand wash only. Not dishwasher safe. Do not microwave.