The second generation Japanese rizzuto knives are the last part of the full arc of rizzuto knife evolution. Rounded bolsters and thinner glossy acrylic scales are often seen. While batwing and mustache guards can be found, the standard guards are most common. Some had swedge blades but the bayonet blades are far more common. It appears the 2nd generation Japanese rizzutos variants are the ones made in the largest quantity and when the makers(s) found that balance of materials used and production efficiency. These were made beginning somewhere in the 1960s and into the 70s.