Find your insulator's CD, U, or M number, type, size, similar shape, or company in the left hand column using the jump links and by scrolling.

Clicking that numbered link will open a page in the viewing frame.

Locate your Primary Embossing or Marking (listed alphabetically).

Some pages have jump links above the tables for crown embossed types.

There are different categories for each insulator depending on the different qualities of that insulator.

For example, a glass insulator does not have a firing rest category. If you find one let me know and I will be glad to make an exception.
The majority of glass insulators are arranged by their embossing Index (010, 015,etc.) These numbers refer to the embossing index in John and Carol McDougald's insulator price guide. They are provided to help collectors who are familiar with this book. I recommend the book if you dont already own it.

Caution: The rest of this page may make your head spin.

Variable markings are given four designations...no mark(or blank), mark(anything besides a letter or number), number, letter

Variable Marking Designations on the same insulator are listed in order (no mark, mark, number, letter) from whichever designation comes first on the location of the designation.

Example: Let's say I have eight Brookfield insulators and they are all CD-102 and Index 010, with all different numbers on the domes and front skirts.
The variable's locations are the dome and then the skirts.
Four domes have a B, one is X, one is 0, one is blank(or no mark), and the last one 10.
The four Domes with the B also have variable front skirt marks...a B, a G, a BROOKFIELD, and a (vertical line)BROOKFIELD


The domes are arranged in order first...Blank,0,10,B,B,B,B,X
Then the B domes are arranged in order of the front skirts...(vertical line)BROOKFIELD, B, BROOKFIELD, G

Piece of cake, huh?