Packed full of new features including a nitrogen-filled midsole, the Glycerin 20 is updated to provide soft and bouncy comfort for countless miles. What You’ll Love Nitrogen-infused DNA Loft v3 is soft yet bouncy Engineered air mesh is secure and breathable Stable underfoot with widened midsole and outsole platform The Glycerin 20 has been updated with a cushioned yet responsive midsole. The nitrogen-infused DNA LOFT v3 compound is built to balance weight, durability, and responsiveness. The upper receives a plush and breathable engineered air mesh upper that provides a secure fit while comfortably holding the foot in place. The midsole and outsole have been widened to offer a platform that is more stable, smoother, and with an easier transition.