From taking the chill out of cool morning bike rides to hiking to the summit of Quandary Peak, you need a versatile layer that works as hard as you do. The Mens Merino 150 Baselayer Short Sleeve from Smartwool is up to the challenge thanks to the body temp regulating properties and breathability of Merino. Featuring Core Spun technology, merino wool wrapped around a nylon core, for added durability while still keeping the comfort of ultra-soft Merino next to skin. Smooth flatlock seams to help minimize chafing and offset shoulder and side seams to lie smoothly beneath pack straps. Performs well on its own in warmer temps or layers up easily when cooler weather rolls in.