On Nokian tires they have tire wear markers, so here is a picture of the tire wear marker. Great tires used them last year with ease getting over Loveland Pass all season long.

 

Do these wheels require hub centric rings?

 

These wheels do have hub rings, and run much straighter then my oem set. I actually thought about getting rid of my oem rims for these last year and would have if they were a staggered set. The advantage of not having a staggers set for winter tires however is that you rotate all four tires and they will last for a longer period of time.