Rear embossing of a common WT baby signal. Was 1943 or 1947 the date these were made? ANSWER 1943 Oct-Dec. Each dot stands for the quarter of the year of manufacture in this date code.

This insulator has a mold number 5 on front. Link [id=220534406] How many different mold numbers do you have? I have 2 4 5 6 7 10 11 13 14 15 and16. Have you seen any other numbers and dots on the rear other than the 43 with four dots?