The Rhythm tee is lightweight and comfortable, perfect for a hike, climb, run or for just hanging out. NuYarn Wool merino fabric is lighter, stronger, more breathable and dries faster than standard merino wool; it's also machine washable. Responsible Wool Standard (RWS) Certified. Slim fit. Crew-neck. 57% nylon/43% merino wool. Quick Drying. Short Sleeve. Weight: 3.4 oz.. Machine wash. Imported.