It is made of silicone. It is naturally harmless, non-toxic with no smells, non-corrosive, and can be recycled. Great Performance in High and Low-temperature Resistance It is applicable to refrigerator and microwave. It is mainly used in restaurants or households to produce spherical ice cubes. The ice cubes can be directly put into whiskey, fruit juice, and beer to chill the drinks instantly. Large Capacity of 160 Ice Cubes It is designed with a big capacity to make more ice cubes. One tray can make 160 ice cubes of 1 square centimeter at a time. It saves more than half of the time of freezing normal big ice cubes. It can be used directly, with no need to be broken into pieces. The tedious steps of ice crusher are removed and your demands are easily and quickly met.