Exclusive dry technology keeps wearer completely dry and comfortable during the entire evaporative cooling process. Up to three days of cooling power to help maintain a healthy body temperature. Fill vest with 13 oz to 20 oz water. Lightweight and durable: made of industrial grade quality nylon. Mesh side-panels provide additional ventilation and stretch. V-neck design with front zipper closure. Cooling material is treated with an antimicrobial that prevents mold growth on the product: always keep cap closed to maintain vest's effectiveness and do not clean the inside reservoir. Reduces the effect of heat exhaustion and fights fatigue while working or playing in the outdoor heat. Machine washable.