Designed to be thirty to sixty percent lighter weight than other cooling vests on the market, the Chill-Its Lightweight Phase Change Cooling Vest helps to keep workers cooler, safer and more productive. Phase change cooling material maintains a 64°F/18°C temperature for up to two hours when activated. Constructed of a polyester cotton blend fabric, the vest's adjustable hook-and-loop closures around the waist provide a customized fit for different body types. The heavy-duty front zipper makes for easy on/off, while the two front zippered pockets can be used to store small accessories. Simply place the four removable packs in a cooler of ice water for five minutes; freezer for eight minutes; refrigerator for 12 minutes; or near an air conditioner for one hour. The cooling pack should be washed by hand with a mild detergent and warm water. Do not machine wash or machine dry. The fabric vest is machine washable with mild soap.