Rolex Explorer ref 5500 a stainless steel wristwatch with bracelet, circa 1963 dial: black calibre: cal. 1530 automatic, 26 jewels movement number: 10133 case: polished tonneau-form, screw down back and crown, inside back date coded 163, no.1002 Closure: Rolex Oyster link bracelet and folding clasp dimensions: 34 mm diameter, internal circumference approximately 170 mm signed: case, dial and movement. Accessories: none the Rolex reference 5500 was launched in 1957 and would carry various names on the dial but the reference is most often associated with the air King model. During a small period of time in the 1960s however, Rolex also produced a small number of reference 5500 watches with Explorer dials that were very closely aligned to the classic Explorer reference 1016. Instead of 'Superlative chronometer Officially Certified' the dials would spell out 'Super Precision' or 'Precision' below the hands, as displayed in this lot. The case of reference 5500 was slightly smaller than that of the later Explorer reference 1016, which went on to become Rolex's longest running Explorer model and was in production from 1963 to 1989.