Ergodyne - EGO12683 6687 Dry Evaporative Cooling Vest offers immediate, dry cooling relief that lasts up to 3 days. Evaporative technology keeps you completely dry and comfortable compared to other vests that require soaking. Fill vest with 13 to 20 oz. (400 to 600 ml) of water for immediate cooling relief. Refrigeration nor gels are needed to cool the vest. High humidity levels can slow down airflow and may reduce cooling abilities. Constructed with high-visibility, industrial-grade nylon to perform in toughest conditions. Design features an elastic hook-and-loop belt that allows a snug, customizable fit. Vest is perfect for anyone working or playing outside in the heat. It is ideal for workers in construction, carpentry, mining, landscaping and more. You can even it while doing activities such as gardening, running, hiking and others. Machine-wash and hang dry for longer life.