UPF 50+ under brim liner. Materials: 100% hand woven straw, polyester under brim liner, cotton drawcord with secured tips and release buckle. Brim length: 3.75" / 9.5 cm. Adjustable cotton twill interior headband. Adjustable drawcord. Anti-corrosive eyelets. One size fits most little kids, ranging from age 2 - 5 years old. Fit measures between (45 cm) - (54 cm). This hat features an adjustable interior headband, allowing for a customized fit. Need a bigger size? Try our Big Kids Signature Lifeguard hat that measures between (47 cm) - (56 cm). We provide guidance on the age range for each hat, but it's important to keep in mind that every kid is different. It's best to measure your kid's head to ensure the best fit. Visit our Size Guide page to learn how to measure your head and find your perfect fit.