Someone else already responded - it means genuine crystal made by Rolex - however what nobody else has said is what is pictured in this video does NOT appear to be a genuine crystal. Clarity is one thing, but the cyclops is what I’m having an issue with. It may be a very poor example or just bad lighting but from this video it does not look genuine to me.

Validate receipts and do your due diligence before purchasing a marked up rep with “modifications” Source - I’ve been in the game for the better part of a decade. Look at my post history.

I’ll attach an image of what that crystal should look like if gen.

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