The Smartwool IntraKnit line is one of our favorite baselayer collections, thanks to a seamless knitting process that creates bodymapped ventilation throughout the garments. The 200-weight version—there are heavier models as well—is a year-round go-to, with testers praising its performance as much on 80°F days as they did on 20°F outings. “When we hit the summit of Mt. St. Helens, it wicked away sweat fast enough that I didn’t get too chilly as it evaporated,” one tester says. Normally $120, the men’s IntraKnit Merino 200 Crew is now $66 (45 percent off) on Moosejaw, while the women’s version is down to $84 (30 percent off).