The Mens Hydropore Half Zip Long Sleeve Top from Jack Wolfskin was made for steep, strenuous ascents, long distance running & other high-output outdoor activities. Wear it as a light fleece or as a base layer next to the skin. The fabric's soft texture gives this top a really pleasant feel. Sweat is quickly wicked from the skin to the outside of the fabric. The high UV protection factor is a real asset in the mountains.