The 661 offers dynamic cosmetics and solid technical features, truly making this shoe a winner. ABZORB in heel is New Balance's top of the line foam material with excellent cushioning and compression set properties. A blend of DuPont Engage Isoprene rubber and proprietary materials provides the ultimate ride. STABILITY WEB structured lightweight arch support provides optimal rigidity preventing midfoot flex. Injection molded EVA for lightweight and cushioning. Ndurance in outsole is rubber compound for maximum durability in high-wear areas. Synthetic/mesh upper for lightweight and support. 3M reflective safety feature. Made in USA.