I believe this is for a rice bowl. It's a dead stock item, so I don't know if it's microwave-safe. It has a sweet, Showa-era construction, and there are traces of stickers. I think there is some age-related soiling. I judged it to be melamine based on the marking on the bottom. I'm not an expert, so I'm not sure. I will ship it in simple packaging. Chicken Indian Kanto Plastic Showa Retro