The sun protection effect of a sun protection hat mainly focuses on parameters such as UPF value, material, and brim size. The higher the UPF value, the better the sun protection performance. Give priority to hats made of tight materials, evenly woven and with sun protection labels, and avoid products made of chemical fiber and other materials. The larger the brim, the better the sun protection effect. It is recommended to choose a wide-brimmed hat. In addition, the sun protection effect of a sun protection hat is also related to the way it is worn. Make sure the hat is worn tightly on the head to avoid direct sunlight irradiating the face and neck. When purchasing, try on the hat to make sure it is comfortable and not easily deformed. In short, when choosing a sun protection hat, you should pay attention to factors such as UPF value, material and comfort to ensure its sun protection effect. When purchasing, it is recommended to check the product description or consult the sales staff for detailed parameters.