white ceramic insulator with marks on top

[dumpicker]

I'm not sure how old this is, probably not very. But is in excellent shape. Can anyone identify marks on top ?

 

[DavidW]

PP INC is for Porcelain Products Inc. based in Carey, Ohio and Parkersburg, West Virginia. The 2nd "P" is missing, and the date is there but the 3rd number is smeared. It is probably 1955. That general "hat" style is nicknamed a "signal" insulator.

Here is a page from Elton Gish (Elton is the number one researcher on porcelain insulators and he has written several books!!). Here, he has a list of companies and the marks they used on their insulators.
https://www.r-infinity.com/Companies/index.htm

 

[dumpicker]

thank you kindly