Smartwool's four-season fabric Merino meets your favorite 1/4 zip style with our Women's Classic All-Season Merino Base Layer 1/4 Zip. With 100% Merino wool next to skin and stretch merrow stitching designed to elevate comfort, range of motion, and fit, you'll feel ready to take on anything at anytime. Select styles feature plant-based-dye technique for more responsible apparel.