Salsa Guide Carbon Seatpost, 31.6 x 400mm, 18mm Offset, BlackThe Guide Carbon Seatpost features a highly adjustable two bolt head design, while remaining lightweight, durable, and supportive when you need it most. Offset design Unidirectional carbon fiber shaft Bonded Aluminum two bolt adjustable head Item Specifications Clamp Style Standard Rails Color Black Defined Color Black Diameter 31. 6 Length 400 Material Carbon Offset (mm) 18 Weight 263 Salsa Guide Carbon Seatpost Seatpost UPC: 657993127148