The California dial is the nickname given to watches that have Roman numerals on the upper half of the watch and Arabic on the lower half, typically with lines at the 3, 6, and 9 o’clock spots and a triangle at the 12. It was actually created by Rolex in 1942, the dial was originally known as the “error-proof” dial, designed to be more easily read because the different style numerals “clearly distinguishes these two halves” of the watch and “the Roman numerals chosen are those which are the simplest to perform and the easiest to read.”

Listed below are f few nice examples of this unusual watch dial.