Asics Men's Gel-flux 3 Running Shoe 100% Synthetic Imported Rubber sole Shaft measures approximately 3" from arch Rearfoot and Forefoot GEL Cushioning Systems: Attenuates shock during impact and toe-off phases, and allows movement on multiple planes as the foot transitions through the gait cycle. SpEVA Midsole: Material Improves bounce-back characteristics and decreases midsole breakdown. Guidance Line: Vertical flex groove decouples the tooling along the line of progression for enhanced gait efficiency. Guidance Trusstic: This Trusstic System: integrates Guidance Line construction for enhanced gait efficiency while providing midfoot structural integrity. DuraSponge: Outsole A blown AHAR rubber compound for enhanced cushioning and durability in the forefoot.