All of our custom made tumblers are HAND WASH ONLY. Epoxy is extremely durable and very strong but unfortunately is not a fan of the dishwasher. Think of your tumbler like a child or puppy- don't leave it in a hot car, the freezer, direct sunlight, or drop it (epoxy can crack upon impact). All tumblers will also come with care cards included, as well as any other items purchased 😊.