These Aeroflow Performance universal slip-on wheel spacers are constructed from die-cast aluminium and designed for use on vehicles fitted with 4 stud hubs. Theseprovide the necessary clearance for custom wheel applications or to increase track width, reducing wheel offset for better overall performance. Some spacers may require the use of longer wheel studs. Ensure you consult an automotive technician prior to installation. These spacers are designed for off-road use only. If you intend using on-road, consult with an automotive engineer as to applicable state laws, compliance, legality and requirements. These wheel spacers are sold in pairs.