Lightweight Training Headwear with UPF 40 Sun Protection. The Swift Air Cap is constructed with lightweight and breathable bluesign approved recycled materials, perfect for moving fast and light on trail or road. Featuring a compact, packable design, the water-resistant Swift Air Cap has a flexible brim for stashing in a hip pack or running vest, while mesh panels provide optimal breathability and ventilation. The quick-release buckle back ensures a secure and comfortable fit, and the internal TransAction headband absorbs and wicks moisture, keeping sweat out of the eyes and face. The perfect companion for grinding out miles on the trail, road, or track, the Swift Air Cap is a must-have running accessory.