The Men's Substratum II Core Stretch. The men's midlayer is crafted from our iLUS Core Stretch, combining 4-way stretch properties for superior freedom of movement. The zip-up hiking top also has a brushed-back finish, which provides warmth and comfort. The antibacterial odour control and quick-drying fabric keep you fresh on the trail. Finished with UV50+ protection. Recycled warm backed stretch fabric with textured fabric panels - Ilus Core Natural anti-bacterial odour control properties Quick drying Full length zip High neck for close fit comfort