drawstring closure Women's sun hats are made of UV-blocking fabric, which filters out harmful UV rays and keeps your skin comfortable even on the hottest summer days. Its extra wide brim helps cover your face, neck and ears to protect your skin from rays. BLACK RUBBER COATING - This summer hat is treated with a UV protective coating with a UPF rating of 50+ to protect you from the sun. COMFORTABLE AND BREATHABLE - Top breathable mesh vents let breezes through, and built-in moisture-wicking straps keep your head cool and comfortable on hot summer days. The adjustable chin drawstring keeps the sun hat in place even on windy days. ONE SIZE FITS MOST - This beach hat is one size, with a head circumference of 21.5"-23.22" and a 5.1" wide brim, suitable for adult women. Packable and Lightweight - This wide-brimmed sun hat is foldable for easy portability and saves a lot of space. It's perfect for the beach, pool, fishing, gardening, camping, hiking, traveling, boating, hunting, safari, picnic or sporting events, as well as working outdoors for all season use.