I am trying to identify this insulator. It has absolutely NO EMBOSSING. Notthing blotted out or faded. Absolutely nothing. It came from the home of a reputable insulator dealer who has been in the hobby for 40+ years, so I don't think it's altered or anything. It's heavy for its size, has wear marks on the grooves, great bubbles, etc.etc.

I've checked the price guide and I can't find a cd this shape without embossing. The closest I found was a 160.4 but only aqua is listed as a color. Any help would be appreciated.