CompCooler Dual Backpack ICE Water Cooling System Flow Control(Backup Unit without Cooling Garment)Smart, safety-conscious motorcyclist';s wear protective clothing, like leather, and during the warmer months of the year that can get uncomfortably hot. That';s where CompCooler can help with its cooling system specifically designed for motorcyclists. The system combines a tubing-lined vest with a liquid cooling system housed in a dual backpack to form a self-contained and convenient thermal regulation device. Available in sizes XS/S, M/L, L/2XL, 3XL/4XL, the vest is a highly engineered breathable mesh garment that weighs a mere 0.5KG (1.1 lbs.), dry weight. It consists of a soft mesh outer fabric and inner liner which is easy to don and comfortable to wear against the body. The liquid cooling system is contained in a backpack that weighs 1.8KG (4.0 lbs.), dry weight. It includes a 5.0-liter removable water/ice bladder, miniature circulation pump, 7.4V 2200mAh rechargeable battery, and On/Off switch. When operating, it';s audible output is 45dBA. Cooling energy is provided by removing the bladder from the system, filling it with water and placing it in a freezer. Once frozen, the bladder is easily re-attached to the system, and with a charged battery pack, Users turn the switch ';On'; and the pump circulates cold water in a continuous loop between the bladder and vest. Depending on ambient temperatures and workload, Users can expect a cooling duration anywhere from 4 to 6 hours with a fully frozen bladder or 2 to 4 hours using ice cubes in the bladder. The battery can last up to 10 hours. Additional bladders and battery packs can be purchased for prolonged cooling. Ice cubes can also be used for prolonged cooling, although the cooling time will be lessened.Features:Stay cool, comfortable, and focused when riding on those hot summer days. Cooling energy comes from freezing the removable 5.0-liter ice bladder or ice cubes. Expect 4 to 6 hours of cooli