ZAWIESZENIE
13.1" (333mm) Standard length; Standard springs; Black anodized. 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.
ZAWIESZENIE
12.6" (321mm) -12mm lower; Standard springs; Black anodized. 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.
ZAWIESZENIE
12.2" (309mm) -24mm lower; Standard springs; Black anodized. 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.
ZAWIESZENIE
13.1" (333mm) Standard length; Heavy Duty springs; Black anodized. 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.
ZAWIESZENIE
12.6" (321mm) -12mm lower; Heavy Duty springs; Black anodized. 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.
ZAWIESZENIE
12.6" (321mm) -12mm lower; Standard 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.
ZAWIESZENIE
12.2" (309mm) -24mm lower; Standard 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.
ZAWIESZENIE
13.1" (333mm) Standard length; 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.
ZAWIESZENIE
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.
ZAWIESZENIE
13.5" (343mm) +10mm longer; Heavy Duty Springs; Black Anodized. 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.
ZAWIESZENIE
12.2" (309mm) -24mm lower; Heavy Duty Springs; Black Anodized. 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.
ZAWIESZENIE
13.5" (343mm) +10mm longer; 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.
ZAWIESZENIE
12.2" (309mm) -24mm lower; Heavy Duty Springs; Black Anodised; 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.
ZAWIESZENIE
444 series shocks - Best. Comes with FST (Frequency Sensing Technology) which dynamically adjusts damping; according to road surface. Top mount threaded hand adjustable preload. 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.
ZAWIESZENIE
444 series shocks - Best. Comes with FST (Frequency Sensing Technology) which dynamically adjusts damping; according to road surface. Top mount threaded hand adjustable preload. 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.
ZAWIESZENIE
13.1" (333mm) Standard length; Standard 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.
412 series shocks: Best value Progressive Suspension shock; great as stock replacement. Nitrogen charged double steel wall body. Multi-staged velocity sensitive valving. Five position cam style preload adjustment. Note: Black 412 shocks may be supplied without lower cover. 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.
ZAWIESZENIE
412 series shocks: Best value Progressive Suspension shock; great as stock replacement. Nitrogen charged double steel wall body. Multi-staged velocity sensitive valving. Five position cam style preload adjustment. Note: Black 412 shocks may be supplied without lower cover. 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.
ZAWIESZENIE
412 series shocks: Best value Progressive Suspension shock; great as stock replacement. Nitrogen charged double steel wall body. Multi-staged velocity sensitive valving. Five position cam style preload adjustment. Note: Black 412 shocks may be supplied without lower cover. 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.
ZAWIESZENIE
412 series shocks: Best value Progressive Suspension shock; great as stock replacement. Nitrogen charged double steel wall body. Multi-staged velocity sensitive valving. Five position cam style preload adjustment. Note: Black 412 shocks may be supplied without lower cover. 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.
ZAWIESZENIE
412 series shocks: Best value Progressive Suspension shock; great as stock replacement. Nitrogen charged double steel wall body. Multi-staged velocity sensitive valving. Five position cam style preload adjustment. Note: Black 412 shocks may be supplied without lower cover. 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.
ZAWIESZENIE
412 series shocks: Best value Progressive Suspension shock; great as stock replacement. Nitrogen charged double steel wall body. Multi-staged velocity sensitive valving. Five position cam style preload adjustment. Note: Black 412 shocks may be supplied without lower cover. 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.
ZAWIESZENIE
412 series shocks: Best value Progressive Suspension shock; great as stock replacement. Nitrogen charged double steel wall body. Multi-staged velocity sensitive valving. Five position cam style preload adjustment. Note: Black 412 shocks may be supplied without lower cover. 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.
ZAWIESZENIE
412 series shocks: Best value Progressive Suspension shock; great as stock replacement. Nitrogen charged double steel wall body. Multi-staged velocity sensitive valving. Five position cam style preload adjustment. Note: Black 412 shocks may be supplied without lower cover. 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.
ZAWIESZENIE
412 series shocks: Best value Progressive Suspension shock; great as stock replacement. Nitrogen charged double steel wall body. Multi-staged velocity sensitive valving. Five position cam style preload adjustment. Note: Black 412 shocks may be supplied without lower cover. 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.
ZAWIESZENIE
412 series shocks: Best value Progressive Suspension shock; great as stock replacement. Nitrogen charged double steel wall body. Multi-staged velocity sensitive valving. Five position cam style preload adjustment. Note: Black 412 shocks may be supplied without lower cover. 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.
ZAWIESZENIE
412 series shocks: Best value Progressive Suspension shock; great as stock replacement. Nitrogen charged double steel wall body. Multi-staged velocity sensitive valving. Five position cam style preload adjustment. Note: Black 412 shocks may be supplied without lower cover. 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.
ZAWIESZENIE
412 series shocks: Best value Progressive Suspension shock; great as stock replacement. Nitrogen charged double steel wall body. Multi-staged velocity sensitive valving. Five position cam style preload adjustment. Note: Black 412 shocks may be supplied without lower cover. 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.
ZAWIESZENIE
412 series shocks: Best value Progressive Suspension shock; great as stock replacement. Nitrogen charged double steel wall body. Multi-staged velocity sensitive valving. Five position cam style preload adjustment. Note: Black 412 shocks may be supplied without lower cover. 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.
ZAWIESZENIE
412 series shocks: Best value Progressive Suspension shock; great as stock replacement. Nitrogen charged double steel wall body. Multi-staged velocity sensitive valving. Five position cam style preload adjustment. Note: Black 412 shocks may be supplied without lower cover. 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.
ZAWIESZENIE
412 series shocks: Best value Progressive Suspension shock; great as stock replacement. Nitrogen charged double steel wall body. Multi-staged velocity sensitive valving. Five position cam style preload adjustment. Note: Black 412 shocks may be supplied without lower cover. 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.
ZAWIESZENIE
412 series shocks: Best value Progressive Suspension shock; great as stock replacement. Nitrogen charged double steel wall body. Multi-staged velocity sensitive valving. Five position cam style preload adjustment. Note: Black 412 shocks may be supplied without lower cover. 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.