Featuring UPF 50 protection that filters harsh UV rays, the Mountain Hardwear™ Butter Up™ 1/2 Zip T-shirt is the perfect moisture-wicking base layer with a buttery soft feel. The half-zippered closure offers easy venting and on/off. This zip-up pullover is styled with long sleeves with low-profile thumbholes, a collared neckline, and a straight hem. Crafted from polyester blend fabric with moisture-wicking properties, this pullover top is fit to be great for layering.