Adjustable SIZE - Small best fits for 54-56CM 21.2"-22"; Medium best fits for 56-58CM 22"-22.8"; Large best fits for 58-59CM 22.8"-23.2".
SPF 50+: this sun hat has passed UPF 50+ test, it could block 97.5% or more of sun UV rays.
4.7" BRIM: wide and long enough to shade forehead, eyes and cheeks from sun uv ray.
LIGHT & VENTILATED: cool and comfortable for summer. The chin cord will keep it stay safe on head in wind.
Crushable & Packable - you can easily fold it and tuck in away in suitcase, great for cruise, outdoor trip, beach vacation and the like. Also it can regain its shape easily, but sometimes you might need steam/ironing machine to reshape it.