1560 (non-hack) / 36mm case (excluding crown) / 20mm lug. This is a very attractive early Datejust with a rare 7777xx serial. Rolex Jubilee bracelet, Ref. 6251H / End 55 / no clasp code. It appears to be a genuine Rolex bracelet, but may be from a slightly later period, possibly around the 1970s.
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