A ref. 6238 Pre-Daytona in scarcely seek 18 karat yellow gold. This was last Rolex to simply say 'Rolex Chronograph' on the dial at 12. In addition, the dial is monochromatic, with a sterile steel bezel and tachymeter on the dial not bezel. All of these austere charms changed in the following ref. 6239 Daytona. Yellow gold examples of the 6238 are widely estimated to account for less than 10% of production, or roughly 300 examples in total.