Thank you for sharing your feedback. We’re glad to hear the knife performed well in terms of sharpness, but we’re very sorry to learn about the rusting after dishwasher use. While some of our knives are labeled dishwasher safe, we generally recommend hand washing and drying promptly after use to help preserve the blade’s finish and prevent moisture-related discoloration. High heat, prolonged moisture exposure, and certain detergents used in dishwashers can sometimes contribute to spotting or surface rust. If the rusting persists or appears significant, we encourage you to reach out to us at hello@zwillingus.com with a few photos so our team can review the issue and assist further. We appreciate you bringing this to our attention.