What Our Gearhead(R) Experts Are Saying:"This is my go-to layer for high-output days in cold weather. The fabric moves with me, breathes like a champ, and never feels restrictive. I've worn it hiking, ski touring, and under a shell while belaying-super versatile and dries fast too."Built for action on and off the mountain, the Skyliner Crewneck Top is a core piece in any layering system. Whether it's early-morning tours or shoulder-season hikes, this technical base layer is crafted with Exten(TM) fabric that combines stretch, softness, and performance in one clean-fitting package. It's loaded with function-driven features-from vented armpits for airflow, to flatlock seams that eliminate chafing, and a tapered drop hem that stays put under a harness or hipbelt. With natural odor resistance, a breathable feel, and smooth next-to-skin comfort, the Skyliner Crew is made to keep up wherever the trail leads.