Button Reflectors in the Maze

Button reflectors on one Interstate shield, but not the other, on Interstate 80/580 in Oakland

The sign, for northbound (technically, westbound) traffic on Interstate 580 as I-580 enters the MacArthur Maze in Oakland, shows the button reflectors in use when the photo was taken in May 2009. Note, though, that the Interstate 580 shield does not use button reflectors. In fact, it appears to be a standard reassurance shield, complete with the California state name.