But, the key differences are on the dial: the registers are different, in their numbering style, the color, and the finish. The one sold by Christie’s (on the right above) has registers that are slightly lighter and more matte finish than this one. In addition, the register numbering is different. Just take a look at the dashes in the seconds register – did you notice how the one sold by Christie’s has even hash marks around the register while on the left watch the hash marks at 20, 40, and 60 seconds are shorter and thicker? The Caso one has the more traditional Singer dial numbering in the style found on vintage watches such as the Omega Speedmaster, Rolex Daytona, Heuer Carrera, and the Ulysse Nardin chronograph we showed you last week.

The numeral fonts are also different in style and location. Take a look at the minute register. The difference in length between the 5 second hash marks and the other hash marks on the one sold by Christie’s is minimal (and equal at 5 second increments) compared to the one on the left, where the 5, 15, and 20 second marks are the longs hashmarks, followed by the 10-20-30, which are simply bold. The Caso one clearly has a seconds and minutes register that more closely mirror those found on the A386, although the A386 ultimately had larger registers and the hour register had a different numbering style. In addition, the Caso watch has longer hour markers (due to the smaller registers) and the central minute and hour hands have lume rather than black on the tips.