Omni-Shade 100% textured nylon poplin on top, sides and brim; Omni-Wick sweatband and mesh vents. Omni-Shade UPF 50 protects you from the sun’s harmful rays. Omni-Wick sweatband and mesh venting actively breathe and pull moisture away from your skin to keep you cool. Adjustable draw cord and toggle at back. Fits most: 21.5" - 24.5"; 3" brim.