Seatposts

Trek-compatible seat mast cap Offered in white and black and a variety of lengths and offsets, the mast cap includes hardware compatible with round saddle rails only. 7x10mm carbon rail-compatible hardware sold separately. Key features: - Ultra-light carbon construction - One bolt head design offers easy fore-aft and infinite angle adjustment - Compatible with all Trek road bikes with round seat masts - 175mm and 135mm lengths - 5mm and 20mm offsets - Aluminum clamp

On leg-burning climbs, crazy fast descents and rolling technical terrain, RockShox's Reverb dropper post enables you to attack the trails like never before. Just hit the hydraulic remote lever for 100–125mm of infinitely adjustable up-and-down saddle movement without ever slowing down! The return speed is easily adjustable by turning a dial on the remote while the triple-lipped sealing system and sealed hydraulic hose keep dirt out for clean, consistent operation. There's also an included collar that limits travel to a preferred height setting. So go ahead and drop your seat a couple of inches for that 30-foot technical section, raise it for that long climb then lower it all the way and get back for that steep descent, without losing your flow.