ASICS Men's GEL-DS Trainer 15 Running Shoe 100% Synthetic and mesh Rubber sole Impact Guidance System enhances the foot's natural gait from heel strike to toe-off Space Trusstic System creates a pocket between the Trusstic System, device and the midsole, allowing for controlled midsole deformation and more efficient foot function Propulsion Trusstic mimics connective tissue in the foot by creating tension as foot enters propulsion stage Biomorphic Fit upper reduces buckling and the potential for irritation Asymmetrical lacing design is an anatomically correct environment that reduces potential for irritation and provides improved comfort and fit