Features:1. How to Activate Color Changing: In order to activate interesting coffee mugs the temperature of the hot liquid should be over 70C/158F5. At that temperature it is possible for the color of the coffee mug to change.2. Careful Temperature Remind - Always habitually have a sip of coffee without notice? Our color changing mug will gradually turn back to black sleeping face when the liquid become cold, from which you can notice if it is cold or too hot to drink.3. Durable High Quality Ceramic Mug - Our mugs is well made with premium thick ceramic, features smooth edges and applied leading thermo-sensitive material printing technology. All these ensure a long time of use, totally food safe and no smelling. 4. A Perfect Gift - Good choice for Thanksgiving, Christmas, New Year, Valentine's Day, Birthday, Father's Day, Mother's Day, Teacher's Day and son on. 5. Please be well noticed it is Hand Wash Only.Attention:(1) It is strictly forbidden to use it in high-temperature places such as microwave ovens, dishwashers, and disinfection cabinets.(2) Do not expose to strong light.(3) Do not soak in water.(4) Do not scratch/wipe the image on the surface of the cup body with hard objects, otherwise the image on the cup body will fall off.Notice:Actual color may be slightly different from the image due to different monitor and light effect. Please allow 1-3cm deviation due to manual measurement.Description:Material: Ceramic Function: discolorationStructure: DoubleMicrowave oven: not availableWeight: 330gSize: As the picture shownBattery: NoColor/Style: As the picture shownApplication: Novelty Gift, for Friendsincludes:1 x Heat Sensitive Discoloration Ceramic Cup