This pink STINGRAY XS-size hat is perfect for UV protection. The inner circumference was 52cm. - Brand: STINGRAY - Size: XS - Color: Pink Ultraviolet (UV) Cut Rate: UPF50+, the highest value according to the standards set by ARPANSA (Australian Radiation Protection and Nuclear Safety Agency). With UPF50+, this hat cuts over 97.5% of ultraviolet rays (UVA and UVB). UPF is a standard that quantifies the effectiveness of clothing in blocking ultraviolet rays, established in Australia in 1992, with the highest standard being 50+. New Zealand and the United States also adopt this standard. About STINGRAY: Australia is a country with very strong ultraviolet rays, and has the highest number of skin cancer patients in the world due to UV exposure. Therefore, UV protection technology is advanced, and countries around the world, including Europe and the United States, import UV-cut products from Australia. STINGRAY is a long-established manufacturer of UV wear in Australia, a leading country in UV protection. They have been researching and manufacturing UV wear since 1986. Their products are widely used in kindergartens and elementary schools in Australia, and are loved in over 30 countries around the world, mainly in Europe and the United States. Thank you for looking.