The SmartWool base layer is the smartest purchase I’ve made to date. Made from merino wool, the base layer boasts both an amazing ability to trap body heat while remaining breathable: perfect for avoiding overheating when performing winter activities. Unlike cotton and polyester, merino wool also retains both these abilities even when wet and neither stretches nor shrinks due to temperature. In terms of material selection, the choice of merino wool conveys the functionality and versatility. However, SmartWool’s appeal extends beyond material design. Thanks to its flatlock stitching, the shirt is not abrasive like other wools and can be worn comfortably for hours without itching or chafing. Moreover, the form-fitting aesthetic, supplied by shoulder panels, rear-body seams, and a simple, solid color, communicates its durability and versatility: the SmartWool can fit into any outfit and keep up even when switching between activities. From a frigid road trip around Iceland to an early morning jog, the SmartWool’s versatile material and form make it key to staying active in the cold.