It's a black Gunto. It was actually used in WW2. This Gunto seems to be a modified version of Wakizashi. Originally it contained an old blade from the Muromachi era, but now it's only the exterior. The remnants of that time remain. Fuchikashira has carps drawn on them, which are made of Shibuichi (an alloy of silver and copper). It is still in the best preserved state. It will shine in your collection.
If the blade is not shown in the photo, it is not included in the item. In that case, only the exterior.
There is a picture taken with a ruler for the size. If it is difficult ...
