I’m not an expert but many years ago, I read somewhere that the 3 horizontal legs on the engraved letter “E” should NOT be the same length.
Apparently the middle leg should be shorter.
But I don’t know if this is true for all Rollies, all years and all variations.
As a side, I Don’t see the benefit of adding a gen caseback on a rep watch. Especially if it’s a suspect gen and costs a fair bit.
It won’t add any appreciable aesthetic benefit to the watch when wearing it or even in the hands (since the bracelet obstructs clear view of the caseback).
Sorry for not being more helpful.
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