The men's long-sleeve base layer Thermowave Merino Active Warm represents a premium active first layer, designed for dynamic sports activities in colder weather, such as running, hiking, skiing, and mountaineering. With an innovative dual-layer construction, it combines the best properties of natural and technical fibers, ensuring flawless thermal regulation and reliable moisture wicking during medium to high-intensity movement.

The advanced hybrid knit with a fabric weight of 160 g/m² consists of 47% recycled polyester on the inside, which ensures exceptionally fast drying and pulls sweat away from the skin, and 42% merino wool and 11% polyamide on the outside for pleasant warmth, softness, and high durability. The natural antibacterial properties of merino wool prevent the buildup of unpleasant odors, ensuring long-lasting freshness even during multiple consecutive days of use.

The shirt features a tailored, athletic fit with a comfortable crew neck, raglan sleeves for unrestricted mobility, and an extended back hem that reliably protects the lower back from the cold. Soft flatlock seams prevent chafing against the skin under backpack shoulder straps, while the ultralight weight of only 210 g guarantees all-day comfort in all weather conditions.