Cool down the stuffiness inside hats and helmets! Reusable, energy-saving solution! Freezes naturally below 28 degrees Celsius!!! Brand new, unopened - Product Name: Ryomimasenka Hat Cooler - About the product: Cooling pad to be worn inside a hat - How to use: Uses PCM material, which freezes naturally at 28°C or below and can be used repeatedly. By setting it inside the hat, it reduces stuffiness in the head and keeps you cool. It freezes naturally at 28°C or below and melts above 28°C. Once melted, it can be cooled in the refrigerator or freezer for repeated use. Can be used in various situations such as commuting, going to school, wearing a helmet, club activities, and gardening. Can be used by children and adults. Does not condense, so there is no need to worry about getting wet. Compact and thin, making it convenient to carry and store. Instant purchase available ⭕️