With a silicon lid, the 5.5 inch high Superman Double Wall Ceramic Travel Mug is not only dishwasher safe, but microwave safe! Now we truly have something fitting of the Super prefix. We had the Super paper towels which aren't nearly as durable as they pretend to be, we had the Super coffee machine but that was ruined when somebody didn't use a super filter, and the Super time clock which wasn't keeping track of anybody's time....BUT NOW EVERYTHING IS OKAY because of the Superman Double Wall Ceramic Travel Mug! My coffee will take much longer to go cold which is important when you are nursing a single cup all day.