This is a pack of six optional hard clutch springs for the Fioroni sliding clutch systems. These are stiffer than the stock springs, allowing you to mix and match spring tension within your clutch setup to provide a higher RPM clutch engagement. With the combination of these new springs and the new "Turbo Twin" clutch shoes, the Fioroni sliding clutch system is even better! One package contains six springs, enough for two clutches.