C_Change: The C_Change membrane is a wind and waterproof membrane which independently reacts to changing temperatures and activities. Depending on the situation, breathability or heat-retention increases or decreases. C_Change is based on an example from nature. It copies the similar effect of a fir cone opening and closing in response to different weather conditions. At high temperatures, or during aerobic activity, the structure of the c_change™-membrane opens as body moisture levels rise. Excess heat can escape to the outside air. Due to the lower level of body moisture development in cold weather or during inactive periods, the structure of the membrane condenses, retaining the heat directly on the body. Shivering or chilling is effectively prevented. For more information visit http://www.schoeller-textiles.com/en/technologies/c-change.html