Sony has made a watch where all visible parts — including the strap — are made from e-paper. It’s very much experimental and has some significant limitations alongside its benefits.

The watch is named FES after Fashion Entertainments Sony. That seems to be a very small division of the company as it funded the project through a Japanese equivalent of Kickstarter, from which it raised only around $30,000. The first completed models are scheduled to go out next May.

It’s definitely a case of form over function as its purely a watch with no “smart” features at all. The only real benefit as compared to an ordinary wristwatch is that as well as changing the style of the watch face, you can change the appearance of the watch strap to match, albeit only in monochrome.

The lack of complex processing or display means the watch has a battery life of at least 60 days and doesn’t have any excessive bulk (this model weighs less than two ounces.) However, because it’s electronic ink, it won’t be visible in the dark and it doesn’t appear there’s any back or side lighting in this model.

The Sony division is also believed to be working on other e-paper wearables including shoes, spectacles, and even bow ties that can change appearance.