If you39ve got a campag multiple speed rear wheel and you want to run single speed for a while just switch the multiple speed cassette for this simple cog and spacer kit and ensure you either adjust or tension the chain suitably the large 10mm wide foot on the cnc machined and drilled steel cog spreads the load over a greater surface area than a straight single cog and will significantly reduce the risk of the cog biting into your alloy freehub splines the superlight drilled splined alloy