It's pretty standard. BMWs have lug bolts, not lug nuts. So, when you remove them there are no bolts supporting the wheels. There is a small lip on the hub that will keep the wheel from just dropping off. Putting the wheels on is slightly more challenging, because you have to get the holes lined up accurately.
"People sleep peaceably in their beds at night only because rough men stand ready to do violence on their behalf." -- Geo. Orwell
2006 330i Sonora w/ ActiveAutoWerke flash tune :-)
2004 330i ZHP Imola/NB - missed
2000 328i TiAg - gone but not forgotten
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