Icebreaker Women's 200 Oasis long sleeve Crewe top is made from 100% merino wool, breathable jersey fabric. This super soft, next-to-skin baselayer offer everyday comfort for active outdoor days as well as warmth, yet a very flattering silhouette. The updated design features underarm gussets and set-in sleeves for added mobility and offsets shoulder seams and flatlock stitching throughout preventing chafing across the spectrum of daily motion.