Sizes: XS7, S7 18, M7 14, L7 38, XL7 12, XXL7 58. The Tilley LTM3 AIRFLO Hat is designed with a medium sized brim that snaps up Aussie style and polyester mesh in the crown for coolness and comfort during hot days and strenuous activities. Made with Tilley Nylamtium, a strong water and mildew resistant form of lightweight nylon, this hat delivers an ultraviolet factor UPF of 50 and has a dark underbrim for glare protection. Constructed of lightweight 100% Supplex nylon Tilley Nylamtium with mesh in the crown for added ventilation Hand sewn using very strong thread all seams are lock stitched so they won't unravel The brass eyelets come from Britain and are the best available Certified sun protection fabric blocks 98% of harmful UVAUVB radiation and delivers an ultraviolet factor UPF of 50, the maximum rating given Secret Velcro closure pocket in the crown to stow away keys, cash or credit card Adjustable, tuckaway, Fore'n'Aft wind cord keeps hat in place Dark underbrim reduces glare from water, sand and pavement Rain repellent except where it's obviously not quite Closed cell foam in the crown adds buoyancy Packable, crushable throw it in your backpack, suitcase or golf bag it comes out looking good! Tilley provides a full 100% guarantee for the life of their hats. They are guaranteed not to shrink, tear or even fall apart Tilley hats are insured against loss. Tilley will give 50% of the original value of the hat for up to 2 years Machine wash on delicate cycle separately or hand wash in cool water Avg. weight: 4oz. Brim measurements: Front and back: 2 34 Sides: 2 38 Import.