Outdoor Research Echo Long Sleeve Trekking Shirt with flipover sleeves for cold fingers and hands or sun protection Ultra Breathable And Lightweight for All 4-Seasons Built from bluesign®-approved and recycled materials and is perfect for everything from fall running and spring ski touring to summer hiking and winter base layers. The lightweight and breathable fabric is infused with UPF 15 sun protection and ActiveFresh™ odor control technology, and the AirVent™ technology provides superb airflow and moisture management. Features a reflective logo, quick-drying fabric, and flat-seam construction for a comfortable fit. Perfect for hikes!