The Zwilling knife is rusty because the protective layer has fallen off. The Zwilling knife series combines advanced German craftsmanship with classic design. It combines elegant appearance and functionality. It is novel, fashionable and dynamic. It is a dream knife for kitchen enthusiasts. Using Zwilling's special formula of stainless steel, the ratio of carbon and chromium reaches the optimal balance, giving the blade both hardness and sharpness, and uses the SIGMAFORGE forging process. The blade is treated with the FRIODUR ice forging process to make the steel structure more stable, the knife is corrosion-resistant and tough, and the blade is more durable and sharp. The innovative wedge blade design pursues optimal stability and makes cutting easier.