This 11 oz "magic" mug has an image of a mother sea otter holding her baby while she floats along the ocean surface. The mug is a dark color when cool..add any warm drink into it and watch as the dark color fades away to reveal this adorable mother with her baby sea otter! When the cup cools down it returns to the dark color until you refill it with another warm drink. Magic Mugs make a unique and special gift for friends and family alike...everyone drinks coffee or tea! Hand washed this mug will last for years to enjoy, safe for microwave. Mug changes at 85 degrees..coffee is usually 140 to 190 degrees .. great for kids to have their favorite hot chocolate in! White strip by handle shows when warm, returns dark when mug cools.