20 oz Stainless Steal Tumbler All drinkware products are created using a sublimation process. Ceramic mugs are microwave safe! Like most drinkware, hand washing is best , the dishwasher heat can fade or run ink over time. In addition, seals and/or lids on stainless steel drinkware cannot be guaranteed after use by customer. Please wash with care. Our products are designed to go with a busy lifestyle, keeping your drinks hot for hours OR cold for hours! Enjoy!