CPR is proud to offer our 2.31 upper pulley kit with 10 bolt hub that includes the patented griptec technology to help ensure zero belt slip out of this pulley. The high quality 10 bolt hub allows easy changing of the upper pulley should you later go very large on the lower and need to achieve a specific blower rpm, the bolts also that are used to secure the pulley to the hub are made out of titanium for amazing looks and a lifetime of trouble free use. This pulley also sets itself apart from the rest as it is machined in such a way that does not require your snout to be turned down to fit it on, therefore making install much easier and saving you the headache of having someone machine down the snout. This pulley is available in the raw billet finish you see or black anodized, just simply specify in the notes when ordering. We also can provide you with the needed belt length for whatever your pulley combo at an additional charge or give you the part number if you wish to source it yourself.