Show your love of the Harry Potter book series with this heat-sensitive color-changing ceramic mug. This beautiful collectible features official book cover art of Harry Potter and the Prisoner of Azkaban. Watch as the exterior of this 11-ounce Harry Potter The Prisoner of Azkaban Morphing Mug magically transforms from black as hot liquid is added, revealing the hidden image in full vivid colors! Do not microwave. Hand wash only. Not dishwasher safe. Mesures approximately 5 inches x 5 inches x 4 inches. Ages 15 and up.