The Performance Lab Baselayer Program represents our lightest and most advanced shirting developed to date, constructed from the world’s first ultra-stretch woven fabric with a 3D merino wool structure. At 95gsm, it pairs a breathable, abrasion-resistant outer face with a thermoregulating wool interior engineered for active ventilation, natural odor resistance, and comfort across a broad temperature range. Crafted from a French-milled wool-nylon blend, it delivers exceptional stretch, climate control, and an ultralight, barely-there feel suited for high performance pursuits.