產品特色： 1. 氣密圈加長加厚，有效增加氣密性，提高使用效率。 2. 修剪帽簷的角度，使帽簷不易外翻。 3. 耐磨矽膠材質，延長使用壽命，不易破損。 Features: 1. The airtight ring is lengthened and thickened, which can effectively increase the airtightness and improve the use efficiency. 2. Trim the angle of the brim, so that the brim is not easy to turn outward. 3. The wear-resistant silicone material can prolong the service life and is not easy to break.