Waterproof Uses W-stretch material Apex Aerobic / This 2-way stretch pants material uses 155T nylon and 44T polyurethane covering yarn for the warp and weft respectively. The use of 174T nylon stainer for the weft yarn gives the material a texture that slightly suppresses the raw nylon feel. Suitable for use from climbing to trekking. GREEN MATERIAL / We select and use materials that minimize environmental impact.