La Sportiva Troposphere Long Sleeve
Here's what other sites are saying:
The La Sportiva Men's Long-Sleeve Troposphere Shirt is packed with all the features you need in a baselayer to help your time in the mountains be successful. The 4-way stretch fabric is given an antimicrobial Polygiene treatment to cut down on funky odors, and the slim-fitting nature of this shirt lets it sit comfortably under any mid or outer layer. Seamless technology all but eliminates chafing during the day, and thumbholes help to keep everything in place.
La Sportiva's Troposphere Long Sleeve Shirt is a base layer designed to keep you warm. Built-in ventilation zones are designed to keep you dry, and antibacterial treatment keeps the smell out.