Ritchey wcs 1 bolt seatpostthe wcs 1 bolt seatpost features ritcheys unique sidebinder single bolt clamp design which provides quick and secure engagement also its wide saddle clamp plate reduces stress on lightweight hollow saddle rails this model also features 20mm of offset to help you obtain that aero race position features material 3d forged tr741 aluminium shaft and clamp low profile head wide saddle clamp rail clamp size 7x7mm offset 20mm weight 195g 27 2mm 350mmbuyritchey