The material is 100% cotton (washed denim fabric). The thickness of the fabric is moderate. Size: hat height: 9 cm, hat: 7 cm, hat circumference: 55-60 cm (behind the adjustable buckle, suitable for most people) This hat is suitable for daily, traveling, outdoor activities, such as walking, cycling, golfing, and also suitable for participating in sports events. It protects the skin from harmful UV rays The adjustable metal shoulder strap is something everyone must have. Wear it and you will never have a headache. This hat is very cute and very suitable for hiking, running and leisure. It is a good gift. Your spouse, family, friends and colleagues, they will like it. It is recommended to wash by hand and wash less. Do not press and rub, not machine wash