STX single-tube design Monotube shock with internal reservoir High-pressure nitrogen gas-charged 46 mm piston diameter Adjustable rebound damping Hose-mounted hydraulic preload adjuster Multiple spring rates available to accommodate a wide range of riders Top-level comfort, rideability, and performance Hard-anodized precision CNC-machined components Low-friction shaft and sealhead design Fully serviceable and repairable - Harley-Davidson Softail Fat Bob 114 FXFBS (2022, 2019, 2023, 2018, 2020, 2021); Harley-Davidson Softail Heritage Classic FLHC (2020, 2018, 2019, 2021); Harley-Davidson Softail Heritage Classic 114 FLHCS (2018, 2022, 2021, 2024, 2020, 2019, 2023); Harley-Davidson Softail Fat Bob FXFB (2018, 2019)