Ergodyne - EGO12577 Made with advanced, PVA cooling technology, 6705CT Cooling Bandana Headbands help you stay cool in warm temperatures or while doing strenuous activities. Evaporative cooling process begins when the nonbulking material is fully saturated with water. After a few hours of wear, reactivate the cooling process by soaking in water again. Hook-and-loop closures hold headbands in place and are easy to remove. Adjust by tightening or loosening onto your head until you get the perfect fit. Original, patented design provides a unique accessory when wearing these headbands.