Halfdays Fay Midweight Merino TopBuilt for warmth from basecamp to backcountry, our Merino Base Layer Top delivers the perfect balance of softness, structure, and performance. Crafted in a midweight 270gsm blend of merino wool and bamboo, it offers natural breathability, insulation, and thermoregulationkeeping you warm without overheating, even during high output days. Designed with a womens specific fit and ergonomic design lines, it moves seamlessly with your body for layered