Exclusive, high usable and lasting NITRUM® stainless steel. Each knife can be identified for cutting a specific food using a system of coloured polypropylene indicators located on the handle. Thereby promoting better hygiene and health for the consumer. Based on European standards. Yellow = Cooked Meat Red = Raw Meat Blue = Raw Fish Green = Salads & Fruits Brown = Raw Vegetables White = Bakery & Diary Products Black = Utility Knife.