Legend Suspension Revo-A Shocks For Harley Softail Revo coils provide improved plush ride quality, control, and resistance to bottoming-out. Their extended coil length has larger sweet spot without increasing overall shock length and the unique spring rate offers the ability to soften pre-load, reducing ride height and maintaining a smooth ride. Revo-A shocks have three external knob adjustments allow fine-tuning of rebound performance for any given rider weight, personal ride quality preference, or personal riding style. Features: All the benefits of Revo shocks plus three external knob adjustments allow fine-tuning of rebound Light to heavy riders can fine tune ride preference Hard-anodized, machined aluminum bodies High-flow piston reacts quickly for improved fluid flow management Deflective disc valved damping self adjusts to frequency and ensures controlled performance Note: A h eavy-duty spring is recommended for 250lb.+ rider and passenger total weight. Also consider heavy-duty if the majority of your riding is two up with a passenger and/or gear.