If you’re checking a Rolex before selling or borrowing against it, don’t remove...
https://web-wiki.win/index.php/How_Do_Buyers_Grade_Rolex_Condition_When_Making_an_Offer%3F
If you’re checking a Rolex before selling or borrowing against it, don’t remove the bracelet yourself. On many models, the reference number is engraved between the lugs at 12 o’clock. Have a local watchmaker verify it, and get any offer in writing.