Since it is a cold insulation material that is colder than ice, it has a cooling capacity of about 1.5 times when used with a holder! Perfect for outdoor activities, sports, camping, fishing, and other hot seasons!Precautions for use Please freeze completely before use. There may be some discoloration due to the natural material, but there is no problem with the quality. Avoid direct sunlight and it is recommended to store in the refrigerator after use. Do not hold it with your bare hands for a long time as it may cause frostbite. [Specifications] Cold insulation material: -16 degrees Time required for freezing: Approximately 8 hours Raw material: Main component Natural polymer (plant) Container: Polyethylene