Fitness Posture 4 features an upright pelvic rotation to go farther, faster. Women Specific Design is engineered to yield better fit and comfort for women. FlexForm design allows the saddle to pivot with the rider's natural pedal stroke. Contour Relief Zone (CRZ) recessed saddle cavity eases pressure on soft tissue. Size Specific Curvature ensures each saddle is designed specific to its width. inForm BioDynamic products optimize your natural movement for sustained, higher performance.