Up for sale is a pretty unique piece. This is a japanese sword fuller maker. The fuller on a japanese sword is called a Bohi. Unsure of if it's for a specific sized sword? It is a smaller piece, but also it seems it would have had wood handles at some point. It has Kanji written on both sides, but my phone can't make it out. I thought it was an awesome piece, but have realized I really can't do anything with it. So I thought I'd pass it on! If you have any questions please feel free to contact me at any time!