"The material is made of 5160 spring steel, which is oil-hardened and retains the oil-hardening effect, allowing the surface to have forging marks and possess a protective layer that does not rust easily. Hardness of more than 56HRC, strong performance, send artificial leather protection case . One-piece formed steel, laser cut and then polished and machined, Machine forging ,followed by final heat treatment" As the item is vintage forged style, so the details are not very well handled, please consider carefully before buying.