H P Marauder's Heat Transforming Mug Ceramic Magic Color Changing Morning Coffee Tea Drinking Mug - Heat Sensitive (11 oz) A PERFECT GIFT - For Harry Potter fans, or anyone looking for a handy place to put their coffee in. Or, buy it for yourself. Treat yourself. Good for coffee, milk, tea and hot chocolate, share with your family and friends HEAT ACTIVATED - Pour in hot liquid and watch the Harry Potter Marauder's Map magically appear. This color-changing mug contains the wizarding worldly spell of Metamorphmagus. In order to activate the mug the temperature of the hot liquid should be over 70C/158F. At that temperature the color of the mug will change to reveal the map 11 OZ CERAMIC MUG with Artwork - Mug is not microwave safe, hand wash only! Placing mug in dishwasher or microwave could ruin the art as for all heat changing mugs. Also we do not recommend leaving mug in soaking water as it could also damage artwork HIGH QUALITY and cool design, this mug will bring a smile to your day when you wake up in the morning and have that first cup of joe, tea or hot chocolate Lifetime Warranty and 100% Satisfaction Guarantee. ADD to CART NOW