Stock Miata wheels are hubcentric. This means that the center bore of the wheel matches the outer bore of the hub, making for a nice snug fit. This doesn't make for any difference in performance, but it does make it easier to install the wheel. Once the lug nuts are torqued, the wheel will center itself on the tapered lug nuts.
6UL wheels have a 67.1 center bore. If you want to make them hubcentric for an NA, NB or ND Miata, you can use these centering rings.
Anodized 6061-T6 aluminum means no corrosion and no melting.
Sold individually, one needed per wheel. Will fit any four-lug 6UL other than the original Gen 1. If you're not sure, look for a 6UL stamp on the face of the wheel. If you find one, these will fit. We're now on Gen 4.
NOTE: if 949 cannot supply these, we will substitute rings from another supplier. They are of equal quality and fit but do not have the 949 branding on them.
They should also work with other wheels with a 67.1 bore, but we can only say for sure that they'll fit the 6UL.