The Endura BaaBaa Merino Long Sleeve Baselayer is a great for year-round use, keeping the chill out on colder days and regulating your temperature on milder days. The 100% merino wool construction is soft against the skin and does a good job of keeping you warm even when sodden with sweat. The flat-lock seams and printed label provide next-to-skin comfort, and wool is naturally odor resistant. Easy care machine washable. 100% Merino Wool.