The Stella McCartney x adidas women’s UltraBoost 21 ‘Signal Orange’ features a sock-like build that effortlessly blends sport and style. The British fashion designer applies a monochrome citrus finish to a minimalist upper composed of 50% recycled content. The breathable mesh construction is fortified with a glossy patent leather toe and TPU heel counter. A supportive midfoot cage extends to the full-length Boost midsole, enhanced with an updated Torsion system dubbed Linear Energy Push. Underfoot, a Continental Rubber outsole provides grippy traction.