Here's what other sites are saying:
Terramar engineered the Men's Midweight Crew Long-Sleeve top as a high-performance base layer to meet the demands of active outdoor enthusiasts. The mini-ribbed knit creates tiny air pockets for superior insulation without excess bulk or weight. The 2-way stretch polyester-Lycra blend allows for maximum freedom of movement and enhanced shape memory, so your shirt stays in the shape of a shirt even after seasons of use. Saddle shoulders, a longer tail and flatlock seams provide a comfortable athletic fit. The patented EC2 Qwik-Dri process grabs water droplets and pulls them away from your skin, yielding much more rapid and effective evaporation than natural wicking. Furthermore, unlike applied hydrophobic treatments, the EC2 process actually alters the molecular signature of the polyester yarn, so you cannot wash it off or wear it out.