The Zeroweight Warm vest is great for the transition season or as an extra layer on extremely cold days. Too cold and windy for long sleeves alone, still warm enough to leave the jacket at home. Designed to shoulder the days in between and protect in extreme cold, this high-performance, extremely light vest is windproof, water repellent, cut with 4-way stretch fabric and comes with the critical details you need to cut through the conditions. The perfect performance vest for your next PB.