Kishigo Brisk Cooling Series® Shoulder Insert ul)Brisk Cooling Promotes comfort and endures safety in high heat conditions.. Provides extended cooling comfort and heat stress prevention. Brisk Cooling is lightweight, durable and reusable. Activated by simply submerging in water. Cooling lasts for 5-10 hours & can be re-activated by re-submerging in water. Simple and easy to use. One size fits most. EVAPORATIVE COOLING TECHNOLOGYSpecialized fabrics and fibers create an advanced water management system, called 'HyperKewl'.HyperKewl absorbs, stores and releases water within the multi-layered structure.The fabrics cool itself through evaporation and a chill effect is created.Users can expect the evaporative cooling fabric to provide temperatures that are up to 15-20degree cooler than the am...