It’s a well-proven fact that cooling the wrist is an effective biological shortcut to cooling the entire body. The Hyperkewl™ material of the Flux cooling wristband stays active for between six and ten hours after activated. The lightweight wristband attaches easily via a Velcro closure and helps keep riders from overheating in hot-weather conditions. User instructions Cooling products with HyperKewl™ Before the first use, please dunk the product under water, gently squeeze out the excess water and let the product dry completely. This is necessary for the cooling fibers to set into the product. Please note, the product could feel 'slimy' because of the fiber migration after the first activation. This rinses away on the next soaking. Outer shell: PWR; stretch mesh. Insulation: HyperKewl™ Polymer Embedded super absorption cooling fabric. Lining PU coated ripstop. Composition: 40% Polyamide, 27% Polymer, 23% Cellulose, 10% Elastane. Fit: tour fit.