Here's what other sites are saying:
You'll grab the REI Tech long-sleeve T-shirt from your closet when heading out for a trail run, going to the gym or taking your first step in seasonal training. Moisture-wicking, quick-drying stretchy fabric features high recycled content. Fabric provides UPF 50+ protection from harmful solar rays. Ergonomic seams reduce chafing. The REI Fleet long-sleeve T-shirt offers a next-to-body, athletic fit.