Rolex "Oyster Perpetual Datejust Superlative Chronometer officially certified", Movement No. D556844, Case No. 5530947, Ref. 1630, Cal. 1570, 36 mm, circa 1978

A gentleman's automatic bi-color wristwatch with date
Case: steel/gold, screw back ref. 1630, screwed "Twinlock" winding crown, steel/gold Rolesor bracelet. Dial: gilt, rehaut with luminous indexes. Movm.: rotorwind movement, Glucydur screw balance.

This vintage "cult model", a Rolex ref. 1630 , is an intermediate reference. The watch looks like an Oysterquartz, but is fitted with the self-winding calibres 1570 or 1575 and was only on the market for a very short period of time. The winding crown is smaller than that of the Oysterquartz and the Rolesor bracelet of the 1630 has three gold central links where the Oysterquartz only has two. Also, the gold from the centre pieces continues on the case. Another important difference are the luminous indexes on the rehaut.