The Women's Sonic LS Zip is built for active days in the mountains, whether were chasing personal bests on trail runs or powering through fast-paced hikes. Its ultra-light Motiv Aero fabric is designed to move with us, offering excellent breathability and moisture-wicking performance to keep us dry and comfortable no matter how hard were pushing ourselves. Lightweight and packable, this long-sleeve top is perfect for multi-day adventures where space and weight are at a premium. Thoughtful features like a deep YKK chest zip for quick venting and hidden stretch thumb loops for extra sleeve security ensure this layer adapts seamlessly to fluctuating conditions. With odor control treatment keeping things fresh over extended wear, the Sonic LS Zip is our trusted choice for high-output activities in any season. Material: Motiv Aero (100% polyester, odor control treatment) Fit: regular Center Back Length: 25.1in Style: half-zip Thumbholes: hidden thumbloops