Baselayer? Outerwear? Let's not get hung up on labels. Our Zepher line has quickly become a favorite with our customers (not to mention with us) as a midweight answer to every question. Featuring soft, sturdy 18.5 micron Merino 230g/m 2 and a semi fit cut, it's a superfine, temperature-regulating baselayer, or sporty, rugged outerwear. Or both. We don't like labels.