"The Tyri Hoodie uses a four-way stretch knit blend of nylon, polyester, and elastane to move with us through hikes, trail runs, and camp days alike. Raglan sleeves keep the shoulders unrestricted, and the fitted hood adds coverage without added bulk. It layers as easily under a shell as it stands alone on a mild day. What Our Gearhead® Experts Are Saying:""I've worn the Tyri under a shell on frosty trail runs and forgotten I had extra layers on. The stretch knit moves with my stride instead of hiking up at the waist, so it never breaks my rhythm mid-run."""