is it a sweater or a tee? this ultra-lightweight top doubles as both. effortless as your favorite tee and built for layering on those crisp fall days. this state of the art seamless top is the ultimate in comfort and knitted to fit flawlessly. thermoregulating and antimicrobial this top is knit from merino wool and recycled nylon. it looks (and performs) on point in the office, at the airport, or on a hike.