Coffee, tea, or any hot beverages are best enjoyed at your own leisure. This 12.8oz self-heating mug utilizes an automatic heating system that will keep your beverages consistently at the temperature of your choice. Not only that, the innovative warming coaster doubles as a wireless phone charger. So, when you aren't warming your drink you can keep your devices running. Get ready to sit back, relax, and take your time with your hot beverages in your ionMug and Charging Coaster. Stay Warm: Your mug will maintain a consistent heat of 122° F while on the warming coaster. Wireless Phone Charging Capability. Use the coaster to charge your mobile phone whenever it is not being used