Super-soft cushioning for supreme comfort. Get carried away in the weightless softness of the Glycerin 21, featuring more nitrogen-infused DNA LOFT v3 cushioning than before. FEATURES: Made with recycled materials equivalent to 5 plastic water bottles. New RoadTack rubber includes recycled silica and is lightweight and durable Additional 2mm of DNA LOFT v3 midsole for a plush ride Supreme softness Now with more super-soft, nitrogen-infused DNA LOFT v3 cushioning that is optimized to be lightweight, responsive, and durable for plush comfort. Improved fit New, engineered warp knit upper is breathable and allows for a flexible, accommodating fit while staying soft against your foot. Smooth, stable transitions The broad platform stabilizes your foot and promotes smooth heel-to-toe transitions.