The year of manufacture is indicated by a dot UNDER the letters of the words 'LAMINATED' or 'TOUGHENED', the last digit only being indicated (i.e. 2 = 1972, 3 = 1973).

The month of manufacture is indicated by a dot, or dots, OVER the letters 'TR' and 'EX' of the word TRIPLEX.

Some examples are given below:

All other marks are Trade Marks, which are of no consequence, and therefore can be ignored.