Breathable mesh and durable synthetic uppers. Lace-up closure. Padded tongue and collar. Breathable fabric lining. Removable ComforDryâ"¢ insole features anti-odor properties for a drier, fresher feel. I.G.S® (Impact Guidance System) employs linked componentry to boost the foot's natural gait from heel strike through toe-off. Rearfoot and Forefoot Gel® systems work together to reduce impacting shock and allow movement in multiple planes from heel strike through toe-off. SpEVA® midsole maximizes energy return and reduces midsole breakdown. Midsole Height: Heel/Toe: 21 mm/11 mm Differential: 10 mm Guidance Trusstic System® increases gait efficiency, while maintaining mid-foot structural integrity. Guidance Line® technology employs a vertical flex groove that decouples the tooling along the line of progression for maximum stride efficiency. DuraSponge® material in the forefoot delivers cushioning and long-lasting wear. Heardwearing AHAR® (ASICS High Abrasion Rubber) is strategically-placed throughout high-wear areas of the outsole. Maximum Support last offers more depth and width throughout the mid-foot and forefoot, making it ideal for runners with higher volume feet or who wear orthotics. Imported.