Historic

1959 base

This is a neat low-number issue.

c. 1977 sample

c. 1979

QQ-A000 was the primary format for several bases.

1979 base sample
1979 base

The 000A-QQ format was used after QQ-A000 was exhausted.
1993 sample, first-generation 3M sheeting

Remake sample of an older format.
1996 sample, first-generation 3M sheeting

Almost correct, but it really should have one more zero on the end, or a separator.
1996 sample, first-generation 3M sheeting

This one is properly formatted.
c. 1994, first-generation 3M sheeting
c. 1995, first-generation 3M sheeting
c. 1995, first-generation 3M sheeting

This is the current format for historic plates.
c. 2002, Avery sheeting

Avery sheeting began somewhere in the 30000 series.
2006, second-generation 3M sheeting
2008, second-generation 3M sheeting

Vanity with suffix number... still has the QQ designator, but stacked instead.