This sale is for one OC Components Mountain Control MC21 dropper seatpost. This is in excellent, fully functioning condition with only the one mark on the fixed section of the post that is shown in the photos. The travel of this post is quoted as 100mm but this is a conservative figure and in reality it can go to about 110mm. Features sealed hydraulic cartridge, cable-actuated remote control, nylon bushings, and waterproof seals. Fully rebuildable with replacement and service kits readily available from Orbea.