The reference 74033 Heuer Monaco was a fully PVD watch that Heuer brought out in very limited numbers in the late 1970s as something of a last-ditch effort to save the floundering line. You can see one above and read more about it here. It didn't work, so Heuer made very few of them. Because of this, these black Monacos (often called Dark Lords) can bring major money - like 48,000 GBP at the Haslinger Collection Sale at Bonhams a few years back or well into the 30s here. To say the black Monaco is the most sought after vintage iteration of this design classic is not an overstatement. They are so seldom seen that the watch is really something of Heuer collector lore.

Then at Basel just last month, we were shown this: