Fabric,Manmade Imported Rubber sole I.G.S (Impact Guidance System) Technology - ASICS design philosophy that employs linked componentry to enhance the foot's natural gait from heel strike to toe-off. AHAR Outsole - Acronym for ASICS High Abrasion Rubber. Placed in critical areas of the outsole for exceptional durability. SpevaFoam 45 Lasting - Employs 45 degree full length SpevaFoam 45 lasting material for a soft platform feel and improved comfort. Ortholite X-40 Sockliner - This premium sockliner features higher rebound properties while providing excellent moisture management and a high-level of breathability (Ortholite is a registered trademark of ATP Manufacturing LLC.) FlyteFoam Midsole Technology - Our FlyteFoam technology provides exceptional bounce back and responsiveness no matter the distance, utilizing organic super fibers to help reduce packing out that traditionally happens with softer, low density foams.