Independent testing have tested and proven that the heat exchange between the cushions and heat source. Which normal body temperature is 98.6 the cooling affect will keep you cool. If cushions absorb too much heat they will become less effective (saturated heat) and will need time to regenerate. If super saturated heat occurs cooling pouches may become damaged. The cushions are designed to be used for many years and will regenerate to keep you cool for many usages. When temperatures are below 77 degrees the liquid will return to a crystal state, ready for next usage. The Bureau Veritas Products Services Inc. completed testing of our product and has given our products Certificate of Compliance. And Non Hazardous Nor Harmful. (Discovery Channel Stores Eye Mask) All of our products use same ingredients as our self cooling eye mask and all of our products.