Rolex

Mark I Daytona:  all models from the introduction of the modern Daytona up to the introduction of the “fat hands” dial which happened mid-way through F serial production

Mark II Daytona:  Fat hands models – the only distinguishing difference between a Mark I and Mark II.

Mark III Daytona:  Models with the minute marker variation (absent are the enlarged 27 minute marker and 33 minute marker as is found on Mark I and II dials).  As of this writing, I’m uncertain when the Mark III dial was introduced, though doing some photo research on eBayand Google photo revealed photos of several D series models with the Mark III dial.  My guess/theory is that the Mark II dial only lasted from half way through the F series production, into half way through the D serial.  Meaning, a Mark II  Daytona may be the rarest example found in modern Daytona production.

Mark IV Daytona:  Has the rehaut engraving and, presumably, the Parachrom Bleu hairspring.