Beloved while sweating on the trail—and sleeping in the tent—the ultrafine merino wool of the women's REI Co-op Merino 185 long-sleeve base layer top is soft  breathable and naturally odor resistant. Winter Hiking Long Sleeve Top, Winter Long Sleeve Top For Hiking, Long Sleeve Tops For Hiking In Fall, Long Sleeve Tops For Fall Hiking, Midweight Solid Color Winter Tops, Midweight Tops For Hiking In Fall, Midweight Long Sleeve Tops For Winter, Layered Long Sleeve, Layer Top