The latest product from Euro Air A/S, Membrane Socks provides for manual or automatic changeover between heating and cooling modes. The sock is fitted with an internal, flexible membrane system, which can cover either the upper or lower half of the internal surface of the sock. The membrane sock typically has more permeable fabric on the upper half, while the lower half is less permeable fabric and is fitted with one or more slot-row diffusers. This allows each half of the sock to be designed for a different airflow and pressure specific to its heating or cooling function.