Smartwool. Our Women's Merino 150 Baselayer Tank loves to adventure as much as you do. This base layer is built with Core Spun technology—which features Merino wrapped around a nylon core for added durability while still keeping the comfort of ultra-soft, responsibly sourced Merino next to skin. The smooth merrow stitching wraps from side to front for a more body-enhancing look—helping you look good and feel good too. And select colorways even feature plant-based-dye technique for a more responsible clothing option. Go Green. Go Far.