with adjustable length and hydraulic spring preload Single chamber pressurized gas compensated (Nitrogen) shock absorber, with oil/gas piston separator. Technical features: Body in Anti-friction trested steel, rod with low friction bushes, and head in Ergal worked from a single block by CNC machine. Setting adjuster: Hydraulic spring preload Rebound (range 7 clicks) Adjustable length (range 10mm) The final code "31" identifies the spring in Red colour (for Sport Bike), and the code "32" specified the spring in Black colour (for Touring/Classic Bikes) Compatible with: - Aprilia: ETV 1000 Caponord_M