“We wanted to have the finest possible pattern traced along the length of the UR-220’s case. We therefore needed a special kind of carbon in layers that are not only parallel but as thin as possible. The concentric pattern on the surface of the UR-220 is the result of this choice. In terms of style and technique this UR-220 is just the way we wanted it.”.
Martin Frei

Not much to say, just that we love their watch sooooo much !