Zipp SL Speed SeatpostZipps SL Speed Seatpost has become a favorite of pro road and cyclocross racers because of its light weight and dependability. UD carbon post, head and clamps Minimum insertion length is 100mm Single bolt adjustment Material: Carbon Clamp Style: Standard Rails, 7x9 Rails Min Height: 100mm Max Height: 240mm Offset: choose; 0mm Length: 400mm Diameter: choose; 27. 2 Weight: 170g. Color: UD Carbon