While looking directly to the left of the embossed letter B are 3 thumb print size depression's all spaced exactly 1/4" apart. [This depression facing upward] in the very center of it has a V shaped mark, not as if intentionally there, but that mark of an imprint was left from the center of some sort of a tong type of a tool that possibly may have grasped the insulator while not yet completely cooled, causing both the mark & thumb size depressions. .

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