The adidas UltraBoost 21 'Grey Screaming Orange' marries responsive cushioning with a sustainable build. The sock-like upper is constructed from breathable grey Primeknit, partially made with recycled materials that include Parley Ocean Plastic. The neutral palette is disrupted by a gradient blend of orange and purple on the translucent heel counter. A redesigned Torsion system enhances the Boost midsole, reinforced underfoot with Continental rubber in high-wear areas.