Science tells us perpetual motion is impossible, yet we see it all the time in some of our friends. So we made the Performance Better Sweater Â¼-Zip for them. Lightweight, warm and motion-friendly, we make this dynamic jacket from 100% polyester fleece fabric with a sweater-knit face and a soft, cozy interior throughout the body and collar so you can scramble talus all day and still look presentable for a trip downtown. Side panels, made of Polartec Power Stretch, have a tough, jersey face for durability and a fleece backing for a skin-friendly feel. The raglan sleeve design, with underarm gussets, allows the full range of mobility. Flat-seam construction reduces bulk and helps eliminate seam chafe. A zippered chest pocket is earbud-compatible. The Â¼-zip design has a zip-through collar for additional warmth and protection. Elasticized cuffs and hem seal in your heat for sunrise starts. Hip length.