Usually the cup body is made of plastic, and the two-layer Cup wall is separated with liquid. This liquid cannot be taken out. It is solidified after being frozen in the refrigerator and used as cooling agent of the beverage in the cup. In order to enhance the appearance, usually colored liquid.

The color of the frozen liquid will fade slightly, and the color will gradually recover during the melting process.

To protect the Cup, the liquid in the compartment will not be filled, and consumers do not have to buy cups with too much liquid.