Roman numerals are a classic feature on the dials of mechanical watches. It is striking that the Roman four, which we know today as "IV", is often shown on dials as four dashes: IIII. A detail that can also be found on the dial of the NOMOS Ludwig model. This is a watch tradition for which there are various explanations.

According to one explanation, IV in Latin was an abbreviation for the god Jupiter, a figure that the mostly ecclesiastical clients did not want to refer to on their clock towers. Another explanation is that of greater aesthetic harmony between IIII and VIII to the right and left of VI, or better differentiation. In fact, denotation of the number four as IIII was quite common in everyday Roman life. The alternative version, IV, was added later. When Roman numerals began to be used on tower clocks in the Middle Ages, goldsmiths apparently opted for the first, more intuitive notation. And then it became a tradition.

Of course, there are also famous exceptions: For example Big Ben, the clock on the Elizabeth Tower of the Palace of Westminster in London, shows IV. Today, however, Roman numerals represent an elevated meaning in every notation. If a number is particularly important, it is written in Roman numerals.