I just got my new Motegi rims & I noticed that there is a package with 4 plastic rings in it (assume 1 for each wheel). I looked through the info for putting the rims on & such & I couldn't find anything. Does anyone know what they're for? I initially thought that they'd go on before the wheel, but I really don't know. Any info would be great, I'm getting them mounted & put on tomorrow.Thanks.