This is an octagonal stainless steel show plate from Sanpo Sangyo Yukawa in Tsubame-Sanjo, Niigata, Japan. Purchased in the late Showa era, it has been used a few times and stored for a long time. As shown in photos 5-6, there are some bubbles and damage on the front and back due to aging, but it has been polished and is clean. Outer diameter: 31cm x 29cm Inner recessed diameter: approx. 18cm Please understand that this is a used item before purchasing. There are 3 more plates of the same type in stock. If you would like to purchase multiple plates, I will offer a discount. Please comment.