There are some minor scratches, but it seems to have been used infrequently and is in good condition. It's an American shank. Information about the size is not available, but the inner diameter is about 17mm, and it gives the impression of a slightly rounded V-cup. The following information is for reference: https://www.hiiron.com/%E3%83%9B%E3%83%AB%E3%83%B3%E3%83%9E%E3%82%A6%E3%82%B9%E3%83%94%E3%83%BC%E3%82%B9%E3%83%AC%E3%83%B3%E3%82%BF%E3%83%AB/%E5%95%86%E5%93%81%E3%83%AA%E3%82%B9%E3%83%88%E8%A1%A8-1/hans-hoyer/ https://paypayfleamarket.yahoo.co.jp/item/c1051942010