Many athletes seeking outright speed favour this more forward position on the bike. Some frame designers are also specifying a slacker seat tube so riders can set their bike up with an inline post, which is lighter than a setback post. The splined alloy Diff Lock coupling is a highly-accurate method of setting saddle angle needing only lightweight clamping by side-mounted bolts. It is especially useful for fine adjustment of saddle setback, which can be done without impacting saddle angle. Ionic‑0 Team Stealth has a carbon fibre shaft bonded into an alloy head & is finished in our elegant Stealth livery. Note: Standard Diff Lock seat clamp fits only saddles with 7-mm ∅ round-section rails. Saddles with oval rails require oval-rail clamp caps.