Review on The Unemployed Philosophers Guild Heat Reactive Constellation Mug - Reveal 11 Constellations with Coffee or Tea - Presented in a Playful Gift Box by Joseph Marshall

I really like my mug. After reading the reviews I was confused as to how it would hold up. Here's the scoop...it's not meant to be washed in the dishwasher or hand cleaned on the outside. When unpacking, there are 2 thin PE films on the outside. The first has a sticker asking to be removed. This protects it from scratches during transport. The second is a thin, semi-permanent pad that reacts to heat. It can be easily scratched or scraped off, rendering the effect unusable. The bottom line is just be careful and don't expect to wash, dry clean or put it in the dishwasher and you'll enjoy the changing novelty effect for years to come. Hope that helps.