Functional underwear is suitable for all seasons. While it insulates against the cold in summer, it provides soothing warmth in winter. It is also highly breathable and odor resistant.
Depending on the season, however, the material is crucial. Polyester or polyamide ensure better cooling performance in summer, and better thermal insulation in winter with merino or merino mix fabrics.
The latter in particular is currently in vogue, as the merino wool fibers ensure a comfortable fit and are kind to the skin. Functional underwear made of merino wool is also available in different forms of processing - depending on the season - which is why these garments are definitely year-round classics.