Drawstring closure [ADJUSTABLE SMART DESIGN]: Sun hats for men and women with adjustable head drawstring for the perfect fit. Simply adjust for your head size using the toggle at the back. [UV SUN PROTECTION]: Sun hats made of 50+ UPF rated high quality water repellent polyester that dries quickly. UV rating is due to weave of the fabric; no harmful chemicals or dyes were used. Reinforced brim designed to stay up. [BREATHABLE & PACKABLE]: Breathable cotton sun hats with mesh panels (Jasper model only) for extra ventilation. Collapses (Jasper model) and folds (bucket and adventure models) to fit in your backpack. Perfect for travel. [REMOVABLE STRAP]: Adjustable chin strap ensures hat stays put when windy with easy toggle adjustment. Strap is detachable via clips on both sides. [SIZES]: All sunhats are adjustable. M: Head circumference up to 57 cm/22.4 inches, Jasper Style M: Up to 58 cm/22.8 inches; L: Up to 61 cm/24 inches for all styles JAN & JUL Adjustable Sun Hats with UV Protection for Women and Men | 4 Styles - BWPZRL8V5