Home Series graters are dishwasher-safe and feature surgical-grade, photo-etched stainless steel blades. Blade made of surgical grade stainless steel. Plastic handle with cover included. Dishwasher safe, however it is recommended rinsing your grater in warm water immediately after each use. The Extra Course grater is used where more texture is required such as vegetables including onion for a frittata, potato for a Hashbrown, cabbage and carrots for salads and soft cheeses like Mozzarella or butter for pastry making.