This travel expert says he never leaves home without a Rolex - but it's not just to tell time

Getty/Astrid Stawiarz

A Rolex can be a great travel tool - for the right person.

• Rolex watches are so valuable, they can be used as currency.
• Philippe Cousteau told Bloomberg that he never travels without it, as everyone understands the value of a Rolex.
• Still, the watch has to be something you can afford to lose.

Expensive wristwatches are invaluable traveling tools. They can tell time, don't need batteries to run, and are incredibly reliable.

Another bonus, according to Travel Channel host Philippe Cousteau, is that nearly everyone worldwide understands the value of a Rolex, and it can be traded in the event of an emergency. Cousteau, who is also the grandson of Jacques Cousteau, told Bloomberg that he wears an understated but "tradable" watch no matter where he goes, because of how useful it can be as emergency currency.

Cousteau is vague about the kind of "trouble" he describes, but we can imagine a few scenarios where a valuable watch would help you get to places on time.

Cousteau says an ex-British special force soldier gave him the advice. We're guessing the advice is a little more useful when you have years of military training and expertise - and look like you do, too.

After all, this advice seems a bit old-school. In all but the most remote corners of the world, access to money is only a phone call or click of the mouse away. Though there are usually fees involved, finding an ATM that will give you access to cash through a credit card advance or debit isn't difficult. And it doesn't involve giving away a prized possession.

If you were to find yourself in a serious emergency, it's not hard to imagine a scenario where a fancy watch would just make you a bigger target. A kidnapper wouldn't free you just becuase you have something valuable - they'd likely just take that from you, too.

For many, expensive watches are investment pieces. If you're bringing it with the thought that you might lose it, you have to be very sure that you can afford to lose it and can purchase another one if you need to.