Custom Dylan O'brien Morphing Mug Just plain black in color when it's cold, this magical 11 oz. mug will turn white and reveal your design only when filled with a hot beverage. Just add your coffee or tea, and watch your images come to life in vibrant color. 100% Ceramic. come in 11 Ounce with black handle. size:3.74 inches (H) X 3.23 inches (W)