Melamine from Marine Business is unbreakable and very light . The dishes can be used on board every day and are always comfortable . The Northwind design is available in round and square shapes. All crockery parts are built so that they can be easily stacked . The round plates, bowls and cups have a non-slip ring so that the dishes stay on the table even when they are in place. Glasses, cutlery and place mats in the Northwind design are also available .