Outlast Temperature Regulation stores and releases body heat.It works to keep the wearer’s temperature not too hot… not too cold… but justright, over a broad range of environments and activity levels.When your activity level or the outside temperature increase, the Outlastthermocules that contain the phase change paraffin begin to change from a solidto a liquid which provides you with a comfortable sensation of thermal equilibrium.The energy required to activate this process comes from your warm body or therising ambient temperature.When you begin to cool down, Outlast thermocules begin to change back froma liquid to solid. In this phase change, the energy that was absorbed by thethermocules while you were active is returned to you.With the new moisturetransfering material Outlast functions in active use too.