Tilley Hat - Broad Brim Hat with All Mesh Crown TM10 ALL MESH CROWN!!!! Blocks Sunlight but allows air to pass easily Mesh has been treated to be water-repellant. 100% cotton duck brim blocks sunlight. UPF 50+ Floats. Machine Washable. Chinstrap & Backstrap. Secret Pocket. Lifetime Guarantee and Insured against loss.