VARIATIONS

1907:     Short base 5654, long base 5727, both "87".

1913:     4-5-digits have 4 slots, not 2.

          5-digits are lighter steel.

          #20000 - 20999 have thinner "C" and numbers, and longer size.

          Normal 5-digits have 2 1/2" wide "C", 3" wide numbers, and 19"

          length; #20000 series have 2 1/4" wide "C", 2 5/8" wide numbers,

          and 19 1/4" length.

1914-18:  5-digits have 4 slots, not 2.

1919:     1-2-digits have smaller legend.

1919-23:  4-digits have no hyphen.

1920-22:  1-3-digits have no dash before date.

1932-36:  All-numeric and 1-letter series have "CONN." in LL

          corner, 2-letter series has "CONN." in center.

1937-47:  All-numeric (1 - 9999) and all-letter (AA - ZZZZ) series

          have tab block slightly to left, not centered.

1942 TAB:  Steel or aluminum.

1947 TAB:  Brass or aluminum.

1957-77 BASE:  FN-9685, JN-8714 have period instead of dot.

1977-2001 BASE:  TT-6935, TW-5028 hyphen, TV 9921, ZR 1037 no hyphen.

                 293 EBL - 289 EBM no hyphen,

                 FOG, 331 FOH - 796 FOV no hyphen, FOV hyphen.

                 ENT = Experimental narrow dies.

1996:  3 sticker varieties.

2001-20 BASE:  3M or Avery sheeting used.