Service Course SL SeatpostDescription Ride smoother, climb stronger, and stay comfortable with the Zipp Service Course SL Seatpost (SPSCSLC2). Crafted from unidirectional carbon, its tuned to deliver more shock absorption than many comfort post alternatives, while still meeting strict strength standards. With two setback options (0 mm and 20 mm), a twobolt clamp that works with all saddle rail types, and a redesigned head for easier bolt access, this seatpost adapts to your