By CCN: The Encrypto watches by Franck Muller, which will cost you anywhere between $9,800-$55,880 to acquire, has a built-in cold storage system. The public address is accessible on the outside of the watch, while to get the private key, you need to get inside the watch.
Not Ideal: Company Provides You A Private Key
You can check the balance using the dial, or scan the public address and put it into a blockchain explorer.
Each timepiece comes as a two-piece “Deep Cold Storage” set, with its own unique public address etched on the dial and a sealed USB containing the private key. | Source: Franck Muller
One question arises: if the public address has to be etched into the watch, that means that watch’s manufacturer at some point has access to the private key. This means a security breach could easily allow someone to swipe whatever funds people decided to store on the devices.
A second complication arises. Unlike a regular Rolex or another piece of fancy jewelry, you can’t ever really sell this watch. At least not with the value-added cold storage system intact. The buyer could never be sure you hadn’t copied the private key and held onto it.
Further, it wouldn’t be advisable to buy one of these watches except directly from the manufacturer, which assumes you trust them in the first place.
Yours For Life
It probably would have been more ideal to use a digital display for the public address so that the user could generate it him or herself. A company called Regal Assets were responsible for the creation of this part of the watch. On this subject, the press release about the Muller watch reads: