A bicycle seatpost,[1] seatpin,[2] saddlepole,[3] saddle pillar,[4] or saddle pin[5] is a tube that extends upwards from the bicycle frame to the saddle. The amount that it extends out of the frame can usually be adjusted, and there is usually a mark that indicates the minimum insertion (or maximum extension). Seatposts can be made of steel, aluminum, titanium, carbon fiber, or aluminum wrapped in carbon fiber.[6]
One(1) bike number, to be attached to the saddle pole.
saddle pillar n. Motorcycling and Cycling the pin extending from a cycle saddle which fits into a socket on the cycle frame.
saddle pin n. (a) any of various pins which fit into a saddle (in various senses) or resemble a saddle in shape (rare); (b) Motorcycling and Cycling = saddle pillar n.