Mount Everest, as you may have heard by now, has been conquered already, but the Rolex Explorer II watch (or Rolex Explorer 2, for the Roman numeral-disinclined) keeps scaling new heights.

As a matter of fact, if you are a mountaineer or an all-around extreme sports enthusiast who needs a no-frills, reliable and robust watch to keep ticking in all kinds of rigorous and unpredictable conditions, then the Explorer will fit the bill.

Just as climbing gear and other sports equipment has evolved in the past half a century, so has the technology and design of the Explorer watch.

The original model created by Rolex in 1953 for the ascent of Mt Everest that may appeal to purists and history buffs, is just a plain steel watch with a 36 mm black dial, a polished bezel, and an Oysterlock bracelet.

The functional models in the current Explorer II line have a 40 mm steel dial in black or white, an engraved 24-hour bezel, and a red hand which, used in conjunction with the bezel, helps the wearer differentiate day from night. It also features a 12-hour hand that can be adjusted to allow for changes in time zones.

All three current models have the same basic minimalist design - uncluttered, clean, and simple. Outdoor adventure seekers do not need - or want, for that matter - dressy or showy wristwatches that would distract them from their exploits. They need - forgive the pun - a truly hands-on watch.

If you are an underwater rather than a terrestrial explorer, keep in mind that, as robust as this watch is, it is waterproof only up to 330 feet (100 metres), so more submersible watches, such as Rolex's Submariner or Sea-Dweller, would be a better choice. And, if you just like the "time zone" feature, and not the overall look of the Explorer, check out Rolex's GMT-Master II instead.

However, for sports enthusiasts who value precision, sturdiness, and a simple design, the watch created for the conquest of the world's highest mountain is still coming up tops.

Current eBay listings for Explorer II watches