Ceramic Maximum temperature differential: 150℃/302℉ Microwave, oven (Up to 300℃/572℉), and dishwasher safe Made in Japan Do not use on direct fire. Do not use ovens that emit direct flame. Heating frozen food in a preheated oven can damage the product, so please thaw the food before heating it. Sudden temperature changes may break or shatter the product. Do not overheat in the microwave or heat without water. The product will be hot when heated. Use mittens to hold. Do not place it directly on the table while it is hot as discoloration may occur. Use a pot mat. Immediately wash and dry well after use, and keep dry when not in use. Wash with care. Do not use abrasive cleansers or steel wool. The appearance of color glaze unevenness varies in each item. Some products may take on a scorched-like texture on the surface. It is a unique glaze effect called "yo-hen", unintended color transformation shows on the ceramic and porcelain after firing. Depending on the manufacturing lot or characteristics of the materials, there may be variations in size and weight for the same product. The size and capacity may differ from what is stated in the product name.