"You may currently have the 6 point allen head bolts attaching your CV's or you may have the 12 point - we offer both of them so you have the option of staying consistent or in case you just have one of the tools. The 6 or 12 point works for all rear cv's whether 2 wheel drive or 4 wheel drive, but only use the 6 points on syncro front CV's as they are just a bit longer as required. "