End link differences

[BuyBackBrandon]

I’m looking to replace aftermarket end links on my 6694 with original Rolex end links. Was hoping someone could point out the difference between 557b and 557 end links and are they the end links that a 1976 6694 with a 78350 bracelet would have come with.

[TimeToGo]

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Either could be used with a case with holes BUT the 557b is designed for the "no holes case" see picture showing the special cut out to remove the bracelet.
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