This is a high quality Reito Bocho style Japanese cutlery knife made in Seki, Japan. Made for professional use, this knife is designed for use with frozen tuna or frozen meat. The blade is made of Stainless Steel and has a curve to cut easily. When you use it, set the blade at right angles to the chopping board, and depress it with both hands. If you twist it or pry the foods open, the blade might break. Has the original model number on the handle.