Here is the top of a two-piece transposition insulator. It is a CD 191 EIN [030] (F-Skirt) AM. TEL & TEL Co [note period only after AM] in light aqua with lots of milky swirls and squiggly lines running all around. It's not mint. There is a 3" long base sliver/chip to the right of the embossing, a base bubble to the left that is open to the inside, and a rear dome fisheye all visible above. Click on View Original for added detail. Do you have a bottom CD 190 that needs a top? Inquiries welcome.