The GEL-Kayano 21 is updated with nothing but the best in ASICS technical innovation, featuring the next generation of FluidRide and a ComforDry X-40 sockliner for the lightest and most luxuriously stable ride yet. Mild to moderate over-pronators will enjoy a more comfortably secure upper, uniquely designed with a new heel construction that complements the premium FluidFit upper and Heel Clutching System. Weight: 8.9 oz. Heel Height: 24mm. Forefoot Height: 11mm.