Sharkskin Chillproof Men's Climate Control Short Sleeve With Reflector The comfortable micro fleece layer is next to the skin to wick moisture and sweat away from the body and keep you dry. The second middle technical layer is 100% windproof, yet breathes to regulate body temperature and stop windchill. The third outer layer is a nylon/lycra blend for abrasion resistance and 4 way stretch. It is also uv resistant for sun protection, and has a durable water repellent finish (dwr) to provide a protective shell that sheds water.