Wilson Rush Pro 4.0 Clay Women's Tennis Shoe - Black/White/China Blue, Size 5.5 US 4D Support Chassis 2.0 splits chassis into two pieces: one running under the foot for forward propulsion, the other running laterally from heel to toe for superior stability and control; Energy Cell comprises a lightweight EVA foam in the forefoot of the midsole to create softer feel and optimal body weight transfer for explosive acceleration; Sensifeel 2.0 features a minimally layered upper with an engineered mesh for enhanced breathability, feel and comfort Women's Specific Support includes asymmetrical and elongated medial side TPU heel counter specifically for women to provide higher levels of stability, arch support and control; Endofit provides enhanced comfort, stability and an intuitive fit through a full inner sock construction DF2 provides cushioned court feel, yielding compromise between comfort and quick performance (DF2 = HT Drop 9 mm); R-DST+ offers the best combination of cushioning and rebound for more dynamic performance Duralast consists of a high-density, consummately durable rubber compound that provides abrasion resistance and maximum traction on all surfaces; Designed for best performance on clay court surfaces.