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 Boy 114 FLFBS (2021, 2018, 2020, 2019, 2022, 2024, 2023); Harley-Davidson Softail Sport Glide FLSB (2020, 2018, 2019, 2021); Harley-Davidson Softail Breakout 114 FXBRS (2019, 2018, 2020); Harley-Davidson Softail Fat Boy FLFB (2019, 2018); Harley-Davidson FXDR 114 (2019, 2020); Harley-Davidson Softail Breakout FXBR (2019, 2023, 2018, 2024)