FSA

KFX Di2 Carbon Seatpost - 350mm Length, 0mm Offset

FSA KFX Di2 Carbon Seatpost is a performance-focused mountain bike seatpost built for riders who want the ride quality of carbon and the clean integration benefits of an internally housed Di2 battery. With a 350mm length and 0mm offset, it’s a smart fit for modern trail and XC builds that prioritize efficient positioning and a tidy, low-clutter setup. Its carbon construction is tuned to balance trail-smoothing compliance with the stability riders expect when pushing through rough terrain.

5 reasons this seatpost makes sense for Di2-equipped MTB builds

1. Internal Di2 Battery Integration - Supports a cleaner, more protected electronic drivetrain setup by moving the battery inside the seatpost (where compatible)
2. Carbon Fiber Construction - Adds vibration damping for comfort on long trail and XC rides without giving up the crisp feel riders want under power
3. 0mm Offset - Keeps the saddle position more directly over the seat tube for a modern fit and efficient climbing-oriented posture
4. 350mm Length - Provides practical insertion range for a wide variety of frame sizes and rider fit requirements
5. Trail/XC-Ready Design - Built for the real loads and impacts of off-road riding while maintaining a weight-conscious build