Despite lots of speculation, it's not known for certain what these abbreviations stand for. On the left is a CD 166 EIN [010] (F-Skirt) E.L.Co. SB Blue Aqua. An open base bubble, some dome scratching, and a ping are visible in the photos. There is also a tiny flake off the edge of the inner skirt. On the right is a CD 102 EIN [010] (Dome) 1 (F-Skirt) S.F. SB in Aqua. I see four tiny dome pecks, and that's it. A couple of well-placed bubbles and a faint steam wisp in the solid dome glass make those easy to ignore. Asking $40 plus postage for this mystery pair.