The Men's Patagonia R1 Air Vest is a technical fleece vest for breathable core warmth in the mountains. No sleeves give this fleece the ultimate in mobility, comfort, and versatility. The lightweight 100% recycled polyester jacquard fleece features hollow-core yarns that wick sweat, dry fast, and maintain comfort during cold-weather activity. The Zigzag-knit pattern increases airflow and reduces bulk, so you can push as hard as necessary between camps or points, as well as pack it away if the day gets even warmer.