has extra wide splines (approx

Must be used with 4-1/2" stroker flywheels

66-84 Shovelhead

front & rear

17-22 Touring

PS, 412 series shock set. 14.25". STD Duty. Chrome 1982-03 Framlampa/Headlight has extra wide splines (approx412 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