New Balance Women's WT875 Trail Running Shoe Synthetic and mesh Midsole Material: Acteva--Superior lightweight foam with exceptional durability. Made with DuPont Engage. 12% lighter than standard foam. Cushioning Technology: Abzorb--Abzorb softens the impact, absorbs shock and displaces energy. Outsole: N-Durance--N-Durance outsole provides long-wearing durability. Recommended Fit: These shoes run True to Size. Classification: Trail