They are shadow wheel nuts, never heard of them and cannot find them on the internet. Also will be changing them shortly
I got them from a place called Scooby clinic near me, a place known internationally for tuning and racing they said they use them on there race cars so I thought I would try them.
But I am not a fan, the coating came of the first time I used them and a couple of the threads have worn off (obviously not on the car now)
The black ones are locking wheel nuts from CS
For wheel nuts check out this thread.
http://www.350z-uk.com/topic/69859-wheel-nuts/