The intersections of Missouri 5 and 6 are among the few intersections of highways that still carry their original designations from the 1922 Centennial Road System that forms the backbone of Missouri's present-day road system. This sign assembly is southwest of Milan, where Missouri 5 and Missouri 6 join for their route around Milan. The concurrent routing ends northeast of Milan.
Also note the narrower digit on the 6 compared to the 5. There seemed to be quite a few such markers for Missouri 6 in northern Missouri in July 2002. Another one was near Dunlap in Grundy County.