COSC Certificate

[Pocosso]

Guys, I have a question, is the COSC paper matching the Warranty?
Is there any serial number on the COSC?
I just Bought A 16520, just wondering if the Booklet set is original.
D.

[Tools]

A COSC Certificate is a pretty unique document and not normally found with a Rolex since it had to be provided separately.

The COSC cert is for the movement and would have the serial of the movement on it, not the watch case. Back when we could order them some research needed to be done to find the movement that matched the case serial and some of them did have both serials annotated. It doesn't have anything to do with the warranty.

[Pocosso]

Understood,
so, in the box, what should I have to find for a 1991 16520?

[Tools]

Perhaps we are talking two different things....

On the Rolex Guaranty (Attestation De Chronometre Officiel ), an early 16520 would likely have a punched serial number, or written in the US, that should match the serial of the watch. This is part of the "papers" and the predecessor of the plastic card.

The COSC Chronometer Certificate is a tech sheet with the pass/fail criteria and movement data as it was tested by COSC.... Completely different from the Rolex Chronometer Statement that is part of the Guaranty

[springer]

Originally Posted by Pocosso

Guys, I have a question, is the COSC paper matching the Warranty?
Is there any serial number on the COSC?
I just Bought A 16520, just wondering if the Booklet set is original.
D.

The chronometer certificate from the company certifying the watch as a chronometer pretty much ended during the late 1960s. Later, on the Garantie paper from Rolex, if the watch was a certified chronometer, the Guarantie paper had a dual function serving both as a warranty guarantee and a chronometer certification. Non-chronometer watches only came with a Garantie on the paper.