The Radius Handlepost is forged from aluminum for strength and features patented Fusion™ technology for an incredibly stiff coupling with the frame and fork. The Radius Telescope handlepost is adjustable so no matter how tall or short you are, you'll get the riding position that is most comfortable. This Handlepost will only fit all Dahon Ahead systems on 20” wheel bikes. It does not include the 25.4mm diameter upper section, the mid Q-release lever or the handlebar itself.