Performance Posture 3 for pelvic rotation with a balance of comfort and efficiency;Hollow Chromoly rails increase compliance for ultimate comfort;Wider cut-out and shaped nose provide a stable comfort in an aggressive position;The Women-Specific Design is engineered to yield better fit and comfort for women;The recessed saddle cavity provides a contour relief zone and eases pressure on soft tissue;Size-Specific Curvature ensures that each saddle is designed specific to its width;Nylon composite shell;