This 18-ounce mug comes with a special charger that uses magnetic induction energy to heat up the metallic layering on the bottom of the coffee mug. Your morning beverage of choice is kept toasty, keeping the temperature around 135º and, better yet, the warming base doubles as a wireless cellphone charger. Includes mug, lid, charger and 12V power adaptor Mug: 5" height, 3.6" diameter, charging plate: 4.1" diameter Mug holds 18 oz. Mug is ceramic; charging plate is aluminum/tempered glass Dishwasher safe Imported