Cooling apparel is designed to assist with Heat Stress prevention by promoting the body's thermoregulation. ~ THORZT Sub Zero Cooling Neck Ties trigger moist evaporative cooling which helps reduce your body's core temperature when working hard in hot conditions. The neck ties contain polymer crystals which expand when wet and can hold up to 500 times their own weight in water. ~ This cold water slowly evaporates from the surface of the necktie, drawing heat energy from the surface blood vessels in the skin as it goes. Cooled blood then circulates back through the body lowering the core temperature and the reducing the risk of heat stress. ~ Submerge your Cooling Neck tie in cold water for 5 to 10 mins then wrap around the neck, head or wrist (ideally at a pulse point) to immediately feel the cooling effect ~ You can also place the neck tie in the fridge or freezer overnight then store in your esky / cooler on site for use later in the work day. ~ Cooling neck ties can be re-used as needed throughout the day by re-submerging in cold water for several minutes. However it should be stressed that whilst this will deliver a refreshing feel, the main benefits of the neck ties come from prolonged evaporative cooling that occurs over long periods. ~ Once the polymer crystal have fully absorbed the water, the cooling effects can last for hours, though the exact length varies depending on the climatic conditions. ~ Promotes thermoregulation ~ Reduces heat stress risks ~ Comforts and cools the skin ~ Looks as cool as it feels.