Smartwool Howelsen Half Zip - Men's wool Men's sizes: Small = 29-31" waist 36-38" chest. Medium = 32-34" waist 39-41" chest. Large = 35-37" waist 42-44" chest. X-Large = 38-40" waist 45-48" chest. XX-Large = 41-44" waist 49-51" chest. 100% merino wool, reverse jersey knit. Hand wash cool, lay flat to dry. 9.5 inch metal center front zipper, relaxed fit, collar with rib interior contrast stripe detail.