Now when I saw these couple day ago, they blew my mind. Simple, yet genius idea! The main highlight for me is wheel bite elimination thus riding completely bug-free.
So these simply go right onto the truck axle and do not touch the wheel at all. As heard from the source- they will run in the $20-30 range per set; will be in different colors; will fit most standard center set and slightly offset wheels up to 75mm; and can withstand being stood on without touching the wheel inside. Me gusta.