True high performance front suspension is finally available for the HD 49mm front ends Progressive Suspension has gone back to the drawing board and created a state of the art Fork Cartridge Kit designed to outperform everything on the market New asymmetrical design places a preload adjuster over a progressive rate spring in one leg and an aluminum bodied, sealed cartridge damper on the other. The result is superior damping and ride control combined with tunable preload and a new benchmark for high performance suspension on the 49mm Dyna and Sportster platforms Can be installed in either configuration, Standard or 1" low available for