The 5 stage adjustable ride height version of the ZERO-1 allows adjustment for all stages for performance and ride comfort. A stainless steel body unit. Recommended for drivers who... want tolower the ride height without sacrificing the stroke length. want to enjoy various setting on road or track or weather conditions by adjusting the ride height, spring rate and pre-load setting to his heart's content. want to try various tires from the production supplied to the S tires. want to take the family bor girl friend along on weekdays comfortably, but wants to challenge that pass or track on weekends. The 5 stage adjustable shock absorbers for more fun driving Stage 1 or 2 : for everyday city use Stage 3 or 4 : for high grip radial tires Stage 4 or 5 : for competition tires