Better fit means better performance. If your saddle is out of position, you’ll waste energy with every pedal stroke. That was our foremost consideration in creating the Service Course® seatpost. The secure, low-profile clamp allows the saddle to slide farther back along the rails, and with 0 mm and 20 mm setback options, it’s possible for nearly any rider to achieve the perfect fit. This unique clamp design also features downward-facing bolt heads that allow micro-adjustment of the saddle even after it is mounted.
For high strength, low weight and efficient use of every gram, the shaft and head are 3D-forged from a single piece of 7075 aluminum â€" not bonded together. The Service Course 0 mm setback seatpost weighs 260 g (330 x 27.2) and is available in 330 mm length and 27.2 and 31.6 mm diameters.
http://www.zipp.com/seatposts/service-course-seatpost--0-/#