SmartWool's best selling and warmest baselayer, just got a little more refined with the SmartWool Women's NTS Mid 250 Pattern Crew Top featuring an improved fit, chafe-free seam construction and panels that offer more comfort with a pack. Benefits: Mid 250: SmartWool's warmest baselayer. Works as a single layer in cool weather or as a baselayer in cold weather NTS: Next To SkinFeatures: Form Fit Interlock knit Back body seam wraps to front for body enhancing fit Shoulder panels eliminate top shoulder seams Flatlock seam construction designed to eliminate chafing Care: Machine Wash Warm Gentle Cycle. Do Not Bleach. Tumble Dry Low. Iron Low or Dry Clean Knit in Vietnam: 100% Merino Wool