Stay warm and dry in cool-to-cold conditions in Patagonia's warmest and most breathable baselayer. Every alpine climber searches for the delicate balance between moving light and fast and staying warm and dry. This lightweight, compressible zip-neck, made of Capilene 4, is the warmest and most breathable baselayer in the Capilene family. It has a soft, stretchy feel, with a smooth-knit face that glides beneath layers. Its open-grid brushed fleece interior warms your core, wicks moisture, and rests smoothly against your skin. Details include articulated sleeves for complete shoulder and arm mobility, hidden thumb loops to ensure wrist coverage, and an elongated front zipper for efficient venting. The drop-tail hem stays put under a harness. Made of 3.8 oz Polartec Power Dry High Efficiency fabric with Polygiene permanent odor control. Fabric is bluesign approved.