The Rolex Explorer II was launched in 1971 chiefly for the speleologists (cave explorers). This version includes a fixed bezel engraved with 24-hour track along with a particular 24 hour (initially orange in colour(currently red) which collectively help to differentiate AM from PM. This feature has been shown to be a boon fo cave explorers. They spend days together exploring deep caverns where daylight is nil. As a result, keeping track of the time becomes hard. Rolex GMT-Master II, an improved version over the initial GMT-Master (introduced in 1954), premiered in 1983. This model is meant for the pilots who need to travel through multiple time zones. It features a particular 24 hour and a bi-directional rotating bezel, designed to display the time of any two time zones simultaneously.
How does the Explorer II Resemble the GMT-Master II?
The 24-hour engraved bezel and the additional 24-hour hand at the Explorer II make it resemble the GMT-Master II. These features between the two empower them to display the time in two different time zones. In the models, the 24-hour hand points to the 24-hour time reflected on the bezel. As an example, if it is 7:00 AM, then the 24-hour hand will point to 7 on the bezel. When it is 7:00 PM, then it is going to point to 19 on the bezel. Another characteristic common to the two models is the “leap hour” attribute. This feature allows the 12 hour hand to be set to another time zone without correcting the 24-hour hand and bezel. This is done by first unscrewing the winding crown and slowly turning it clockwise or counterclockwise. This adjustment will cause jump of the hour hand one hour at a time without stopping the seconds and minute hands. In addition, the independently adjustable 12-hour hand permits the wearer to simultaneously check the time in any two time zones.
The initial Rolex Explorer II version had the same caliber motion as that of the GMT-Master 1575.
Some other common in the two comprise the following:
* Mercedes hands in place of older, big pole palms
* A thinner, scratch resistant synthetic sapphire crystal
* Crown guards
* Self-winding and watertight to 100 meters/330 feet
The significant difference between the Explorer II and the GMT-Master II is that while the Explorer II comes with a fixed bezel, the GMT-Master II includes a bi-directional rotating bezel.
The other areas where the two differ from each other are cosmetic in nature. Also, there are lots of dial up options available from the GMT-Master II, including the Explorer II, which is available in only black and black dials.