“Ziiiro’s line of Gravity and Mercury watches, which are silicone-bracelet-style and stainless-steel-mesh-band-style watches, respectively. Rotating thick and thin swirls take the place of hands, and if you get bored of the color, you can swap the swirls out for others.” Ziiiro Watches: Time doesn’t fly, but it swirls - Core77
..and so are these.