This bangle is a representation of turbulent flow of a liquid over a moving surface. The inside of the bangle -- representing the moving surface -- is smooth, while the outside is curved with the loops and whorls of the turbulence. This is the second in a series of three designs that illustrate the same turbulent flow at different moments in its development. In this middle design the flow has become turbulent everywhere, so it doesn't have as many smooth areas as the first design, but the turbulence isn't fully developed yet so it isn't as gnarled as the third one.
This model is 2.3 inches (59 mm) across on the inside. I'm happy to resize it for larger or smaller wrists; just ask! The bangle is only slightly flexible.