Brooks Glycerin Flex: total freedom for your feet The Glycerin Flex is designed for runners who want maximum comfort on asphalt. Thanks to its innovative cushioning and flexible grooves in the midfoot, these shoes let you run by your own rules with an adaptable, soft fit. Surface: Asphalt Shoe type: Neutral Use: Training Weight: 258g Drop: 6mm Cushioning: Nitrogen-injected DNA TUNEDShow moreShow less