====== Rolex Explorer II 16550 ======
{{wst>image_r|Rolex_Explorer_II|Rolex Explorer II 16570 (black)}}
  *See Also [[Rolex Explorer II]]

**Ref. 16550** was the "transitional" **[[Rolex Explorer II]]** produced between [[1985]] and [[1988]].

===== Overview =====
[[Rolex]] introduced the [[Rolex Explorer II|Explorer II]] series in [[1971]] to complement the [[Rolex Explorer|Explorer]] line. It features an additional 24-hour hand like the [[Rolex GMT-Master|GMT-Master]] but the bezel is fixed in place. This 24-hour indication, among other things, has been designed with regard to professional cavers, for whom a reliable temporal orientation independent of the outside world is of the utmost importance. Accordingly, at the design of the dial a special emphasis was put on excellent readability, even in the dark.

This original [[Rolex Explorer II 1655|Explorer II Ref. 1655]] used a 39 mm case, but this new Ref. 16550 has a larger 40 mm case. In keeping with its sporting intent, it used an [[Oyster bracelet]] and featured [[crown guard]]s. The bezel is marked with numerals at even numbers between 2 and 24 and triangle markers between. The dial is similar to the contemporary [[Rolex Submariner|Submariner]] with a large triangle marker at 12 00, large bar markers at 6 00 and 9 00, and smaller dots at the other hours. There is a date window at 3 00 with a [[cyclops]] magnifier. The hands are Rolex "Mercedes" style, with the [[24 hour hand]] using an arrow point.

The design of this "transitional" Explorer II diverges greatly from the original Ref. 1655. The dial and hands are much more conventional, looking more like a Submariner or GMT-Master than the old model. The iconic huge orange triangle shaped 24 hour hand is also gone, as is a great deal of [[lume]] from the dial. And the bezel is marked with triangles between the even hours rather than stick markers. One upgrade was the addition of a [[sapphire]] crystal.

Another novelty was the availability of a white dial in addition to black. The paint used on the white dial is prone to fading, making a cream color that has become very desirable to collectors. Along with the orange-handed Ref. 1655, this cream dial Ref. 16550 is the most desirable Explorer II today.

For the first time, the 24 hour hand is independently adjustable, thanks to the new [[Rolex 3085|Cal. 3085]]. This means that the Explorer II can now display a [[second timezone]].

Rolex redesigned the movement and updated most of their watches in the late 1980s. The Explorer II was upgraded to become [[Rolex Explorer II 16570|Ref. 16570]] in [[1989]], after just a few years of production.

<WRAP ud ud_mod>
**Reference:**
  * 16550 (steel)
  * Production [[1985]]-[[1988]]
  * Predecessor [[Rolex Explorer II 1655]]
  * Successor [[Rolex Explorer II 16570]]

**Movement:**
  * [[Rolex 3085]], [[self-winding]] 28,800 A/h
  * Certified [[chronometer]] ([[COSC]])
  * 27 [[jewels]]
  * [[Power reserve]] 42 hours

**Case:**
  * [[Oyster]] case, [[stainless steel]]
  * Ø 40 mm
  * 24 hours [[bezel]] fixed
  * [[Sapphire crystal]] with date loupe
  * [[Screw-in crown]]

**Dial:**
  * Black or white dial
  * Red central 24-hours hand with white triangle as pointing arrow
  * Indexes and hands with [[luminous]] color 

**Functions:**
  * Hours, minutes, [[central seconds]], date
  * Independently adjustable central [[24-hour]] hand ([[second time zone]])

**Bracelet:**
  * [[Oyster]] bracelet in [[stainless steel]] with [[folding clasp]]
</WRAP>

===== Literature =====
  *[[Das ZEITGEFÜHL-Uhrenbuch]]; Author [[Gerd-Lothar Reschke]]; ISBN 3-938607-61-0

===== Weblinks =====
  *[[http://www.uhrwald.de/explorer2.htm|Die Geschichte der Rolex Explorer II]], uhrwald.de (German)
  *[[http://www.r-l-x.de/wbb2/thread.php?threadid=79445|Zur Historie der Explorer II]], R-L-X-Forum (German)


{{tag>Watch_models GMT_watches Rolex_models Rolex_Explorer_models}}