The Legionnaires Work Hat with Neck Flap is perfect for a variety of occasions, from outdoor adventures to working on a construction site. Its ultra light and breathable 100% Polyester material makes it comfortable to wear alone or with a helmet, and it won't compromise the function of the helmet. The brim of this hat is UPF50+ rated, providing excellent protection from the sun's harmful UVA and UVB rays. The 11. 5 cm brim size and 15. 5 cm neck flap are designed to protect your face and neck without obstructing your vision. The Legionnaires Work Hat with Neck Flap is also designed to wick away sweat and keep you cool, with fast moisture ventilation through the breathable mesh on the top of the hat and the neck flap. The neck flap also has breathable mesh on both sides to expel perspiration and keep you cool. This Legionnaires Work Hat with Neck Flap has an adjustable head circumference size of 56 62cm. The internal rear drawstring on the crown allows you to customize the fit and keep the headwear in place. The Legionnaires Work Hat with Neck Flap is also easily packable/portable for storage in your backpack when travelling.