A Windjammer membrane is an ultra-thin layer laminated to the shell fabric of the garment. It delivers complete windproof protection, eliminating the wind chill that lowers your core temperature. It does this while being fully breathable.
Micropores that are 900 times larger than water vapour molecules allows perspiration to escape with ease. And a hydrophobic membrane coating prevents external moisture reaching your skin. This ensures a greater degree of comfort during highly active pursuits.