Mount to Coast's R1 isn't messing around. After setting the bar with Meg Eckert's 603-mile women's six-day world record and Matthieu Bonne's 48-hour record just weeks later, this shoe is built to shatter limits. We partnered with BASF to engineer ZeroSag, a revolutionary midsole insert that delivers smooth, responsive cushioning in any condition. Paired with LightCELL—our nitrogen-charged supercritical foam that's 50% lighter than EVA with 45% more energy return—your feet stay fresh for the long haul. GOFLOW geometry keeps your stride natural and efficient, mile after mile. A wide toe box and broad platform give swollen feet room to breathe, while the TUNEDFIT Dual lacing system lets you dial in the perfect fit across your forefoot and midfoot independently. Double-layered jacquard fabric wraps your feet in softness without the weight. Made with 40% recycled polyester, the R1 proves you don't have to compromise on performance or sustainability.