12.6" (321mm) -12mm lower; Heavy Duty springs; Black anodized; RAP (Remote Access Pre-load). Great replacement single shock. Manufactured with a high pressure nitrogen filled black hard anodized aluminum body; with a large 46mm bore and deflective disc damping. Comes with Regular threaded or RAP (Remote Adjustable Pre-load) located behind the left passenger peg; for easy accessible adjustments. Rebound damping is 5-position adjustable. Available in stock; over and undersize lengths to accommodate the various stock Softail model lengths. What are Progressive Suspension''s ''Heavy Duty'' shocks? If you are a lightweight rider with a lightweight passenger; STD Duty is probably your best choice; heavy duty shocks will give you a harsh ride. For Big Guys & Gals with a lot of baggage; Heavy Duty springs are the way to go. Heavy Duty is not better; it''s different.Heavy Duty shocks or springs are recommended to be used on motorcycles that are operated at or near the manufacturers maximum load rating over 50% of the time.