The Bikron watchface is modeled after a clock made in the late 1970's by John Wells of Media House Corporation, Columbus, Ohio.The clock is a Binary Coded Decimal (BCD) display which is read vertically, with the Least Significant Digit (LSD) at the top. There are five columns: hours, tens of minutes, minutes, tens of seconds and seconds.
The hours column uses all four bits to count from 1 to 12.