Launched in 1937, the Patek 533 was offered alongside reference 130 but features a flat bezel and is much rarer than its counterpart with scholars estimating that only about 125 examples were made in yellow gold (interestingly the pink gold version was made in about twice that number). Never offered on the market before, this example has been well preserved still exhibiting a crisp hallmark to the side of the case and an original dial.