The Fresh Foam X midsole foam features around 3% bio-based content, providing an exceptionally comfortable cushioning experience. This bio-based content is derived from renewable resources, contributing to the reduction of our carbon footprint. The upper of the shoe is constructed with engineered mesh. Please note that the 4 mm drop may have slight variations due to the intricacies of the development and manufacturing procedures. Rest assured, every detail of these shoes is designed to ensure 100% comfort.