Extremely light and thin Teflon membrane Gore-Tex. It is waterproof and breathable, yet windproof. The material itself is water repellent, each membrane pores are 20,000 times smaller than a drop of water, while a 700-fold greater than the molecules of water vapor (sweat). Wind resistance is due to a labyrinthine structure of the membrane, which constitutes an insurmountable obstacle to the wind. More information about Gore-Tex can be found here.
