The CST-01 makers say their watch is the thinnest in the world. The CST-01 ($129) comes in at .80mm thin. The time is shown with an E Ink display housed in a single piece of stainless steel. In order to keep the watch as thin as possible, there are no buttons or knob on the watch itself. All of the charging and time adjustments are made from the included base station. It only takes about 10 minutes to charge the CST-01 and the charge will last up to a month. The CST-01 comes in either black or white.