Progressive Suspension 444 Series Shocks Heavy Duty 13" Chrome #444-4071C PRODUCT DETAILS After more than a decade of ruling the roads with our road proven 440 Series shocks, Progressive has unveiled another breakthrough design. Dubbed Frequency Sensing Technology (FST) for its unique ability to dynamically adjust damping as you ride. The result is superior performance no matter the road conditions. A top mount threaded preload adjuster allows for fine tuning with a simple twist of the cap. Frequency Sensing Technology (FST) allows the shocks to sense the frequency of a bump and automatically adjust damping for superior ride quality Deflective disk valving Adjust spring preload by hand with no special tools needed Progressive rate spring Lifetime Limited Manufacturer's Warranty Sold in pairs Made in the USA FIT GUIDE MODEL444 SERIES SHOCKCOUNTRY OF ORIGINUSAFINISHCHROMELENGTH13 IN.QUANTITYPAIRSPRING RATEHEAVY DUTY PRODUCT FITMENT This item fits the following applications: Harley Davidson VRSCAW V-Rod 2007-2010 Harley Davidson VRSCD V-Rod Night Rod 2007-2008 Harley Davidson VRSCDX V-Rod Night Rod Special 2007-2016 Harley Davidson VRSCF V-Rod Muscle 2009-2016 Harley Davidson VRSCX V-Rod 2007