The Smartwool Merino ¼ Zip is our favorite baselayer this year. Winning our Editor's Choice award, this top will keep you warm while you tackle high peaks or descend snowy slopes. The 100% Merino wool construct is comfortable and warm providing a wide range of thermoregulation in temperatures ranging from the double negatives to the sunny 70s. We wore it while hiking, biking, running, and skiing. In all situations it did great, drying quickly and keeping us relatively dry even when we sweat hard.
While the Smartwool Merino 1/4 Zip features the same materials as the Smartwool Merino 250 Crew, our Top Pick for everyday wear, it proved to be more versatile with better overall performance. The crew cut collar of the Smartwool Merino 250 Base Layer doesn't provide as much warmth nor as much versatility when adventuring into the backcountry. Our testers typically chose the Smartwool ¼ Zip during the winter adventures because of its added protection, warmth, and venting capabilities. The crew-neck was typically preferred for hiking and wearing out around town.
If you're in search of a single base layer that can be used for a plethora of activities, the Smartwool Merino ¼ Zip is our best recommendation. While it's not as durable as the Arc'teryx Rho LT or other synthetic layers, it most certainly provides better thermoregulation and warmth overall. A perfect year-round base layer for any outdoor adventure.