Monster Mug was established as a boutique ceramics studio producing with completely original designs. The production process is completely handcrafted. All details and textures are shaped by hand. Therefore, the product you receive is only for you. Stoneware mud is used in the production process. Glaze firing is done at 1200 degrees. Therefore, the surface is fully consolidated and becomes durable. The dyes and glaze used in production are completely safe and food-safe. You can safely use it in hot and cold drinks.due to the high degree of firing and material quality, each mug is 100% dishwasher safe and microwave-safe. However, we highly recommend gently hand-washing your mug after each use.