The ref. 533 was launched in 1937 and stayed in production until 1957. As an alternative to the more well known ref. 130 chronograph, the ref. 533 has only one aesthetic difference to the iconic chronograph: it has a flat bezel much like we see on the ref. 570. The result is a thicker and bolder look than the thinner concave bezel on the ref. 130. The cases were made by Vichet, the dials by Stern Frères, and the movement used was the elegantly functional caliber 13-130. Over 1500 ref. 130s were made during its production run from 1934 through the mid 1960s. With the ref. 533, approximately 330 examples were made exclusively in 18K yellow and pink gold. Interestingly, the ref. 533 was more commonly made in pink gold and yellow gold examples are far rarer. Only 44 examples of the yellow gold ref. 533 are known to exist today. This example was last seen at auction in 2006 when it was ‘fresh to market’ and sold for 78,000 CHF.