Size (approx.) 23 cm diameter x 3 cm thickness It's thick but lightweight. I remember buying this about 30 years ago at Takei Kogei in Nagano Prefecture. I've only used it a few times, but I've stored it stacked for a long time. The surface is relatively clean, but the back has many scratches. Please forgive any slight differences in color between the actual item and the photos, and any minor details that are not fully captured in the photos. This is a used item that has been stored at home for a long time, so thank you for your understanding. I will wrap it in cushioning material and ship it. (Anonymous shipping)