Guys,

Looking at a set of wheels with a 57.1mm hub bore. My car is 56.1mm.

Is it recommended to get a 1mm ring or will the conical lugs hold the wheel on properly and distribute load without a ring?

And if a ring, what type - plastic, metal? I don't want anything to rust onto the hub or the wheel.

I've used rings before, but when the difference was 5mm.