Patagonia R1 Thermal Bottom - Men's Black, XL

What Our Gearhead(R) Experts Are Saying:"Cold days with a lot of stop-and-go are where these really shine. They hold warmth when you're standing around but dump heat fast once you start moving, which makes them far more versatile than heavier fleece."Early starts, frozen approaches, and long hours spent moving through cold terrain demand layers that don't overcommit, and that's exactly where the R1 Thermal Bottoms fit. We rely on them when conditions are sharp, and the effort stays high, trusting them to keep us warm without ever feeling heavy or restrictive. They're the kind of layer that quietly disappears once the day gets going. The smooth outer face cuts wind and sheds light snow, while the soft microgrid interior manages moisture as the pace fluctuates. Stretch through the legs keeps movement natural, whether we're climbing, skinning, or hiking uphill, and the streamlined fit layers cleanly under shells or pants. The R1(R) Thermal Bottoms feel purpose-built for cold environments where efficiency matters.