Zipp service course seatpost better fit means better performance if your saddle is out of position youll waste energy with every pedal stroke that was the foremost consideration in creating a secure low profile clamp for the service course seatpost that allows the saddle to slide farther back along the rails this unique design also offers 20mm of setback and micro adjustment with downward facing bolts that are accessible even if the saddle shell covers the top of the seatpost for high stre