The GKTECH 3mm slip on spacers allow for adjustment of the fitment of your wheels. The wheel spacers are hub centric to suit Nissans 66.1mm hub and are manufactured to the highest quality in T6061 Aluminium and then hard anodized to further increase the strength - CNC machined aluminium T6-6061 construction - Hub centric to suit 66.1mm Nissan hubs - 114.3mm PCD with both 4 bolt and 5 bolt holes - Available in 3mm, 5mm, 8mm, 10mm, 15mm or 20mm (this listing is for 3mm) NOTE: Sold as a PAIR   Do I need longer studs to run these wheel spacers? Probably not. This comes down to your wheel choice (they all differ a little in design), the rotor hat thickness (can vary a little between brands), and the wheel nuts you're running. In most cases I'd say it's probably safe at 3mm to not run extended studs but it is situational and we do suggest checking that you do have ample thread when securing your wheel nuts. If you aren't sure, take your car to a professional. Do you sell spacers with other bolt patterns? No, if it's not listed on our website then we don't sell it. We don't do any custom work. Sorry What hub size are these spacers made for? These spacers are made to suit Nissans which are 66.1mm and as such the spacers have an ID of 66.1mm https://www.iraceautosports.com/product/gktech-13-0mm-knurl-20mm-extended-wheel-studs/ https://www.iraceautosports.com/product/gktech-14-3mm-knurl-20mm-extended-wheel-studs/