The new SL-K SBS SB0 seatpost is lighter and stiffer than ever. Using a UD carbon shaft with a bonded alloy head and a sophisticated SBS clamp design, we can achieve what we believe is the finest SL-K seatpost yet. Available with a polymer Di2 battery holder. - UD carbon shaft with bonded alloy head - Forged alloy "SBS" 2-bolt head - Chromoly hardware - 20mm setback - Fits 7mm standard rails and 7x9mm oval rails - 221 grams