Performance Posture 3 for pelvic rotation with a balance of comfort and efficiency;Unique suspended rail construction increases compliance for ultimate comfort;Strategically-placed, multi-density padding for optimal comfort and performance;Recessed saddle cavity provides contour relief zone and eases pressure on soft tissue;Size Specific Curvature ensures each saddle is designed specific to its width;Carbon fiber-reinforced shell strikes a balance between strength and light weight;inForm BioDynamic products optimize your natural movement for sustained, higher performance;Requires oversize rail-compatible seatpost and seatpost ears;