The ice tray is made up of food Grade Silicone. Flexible and durable Silicone allows for easy removal of ice cubes. Each tray makes up to four large 2″ x 2″ ice cubes. Trays are small, square, and stackable. Takes up less space than conventional ice cube trays. Larger cubes means slower melting and less dilution in your drink. Fill with water or your favorite juices for flavored cubes.