Herculean Advance

Advance exit sign for California 4 at Interstate 80 in Hercules

Button reflectors show up clearly in this photo of one of the advance signs for the California 4 exit from Interstate 80 in Hercules. This photo was taken in May 2009, when, along Interstate 80 in Contra Costa County, there was a mix of button-reflector signs and signs with reflectorized sheeting.