Patagonia Merino 2 Lightweight Zip Neck Shirt - Women's 2012: Worn as an underlayer at dawn and a stand-alone by noon, the supple Patagonia Merino 2 Lightweight Zip Neck Shirt has articulated seaming and a luxuriously soft feel against the skin. Patagonia’s most versatile merino baselayer fabric, Merino 2 keeps you dry and comfortable during active pursuits in cool to cold conditions. It's naturally breathable, regulates body temperature, has a great warmth-to-weight ratio, stretches, and naturally resists odor, allowing you to worry about more important things…like how you’re going to get off a freezing cold mountain.