The Icebreaker 260 ZoneKnit 1/2 Zip Long-Sleeve Top combines thermal-weight insulation with plenty of mobility and breathability for high-intensity activities in cold weather. Warmer than the regular Oasis baselayer the 260-weight merino wool weave is naturally odor-resistant and breathable wicking away moisture and insulating even when wet. On top of that the ZoneKnit construction concentrates insulation where it's needed most with lighter mesh panels strategically placed for added breathability. That adds up to a high-performance thermal base layer that's at its best in winter sports that alternate between low-intensity and high-intensity activities.