Peppo
179
I've found very appropriate this thread
as 6536/1 and 5508 have been born from the same concept ..... a light, so wearable, submariner watch.
Yes, it's right also that some other references from Rolex and Tudor are similar to them, but if I can say which one is the natural son of the other I would say this couple with no doubt.
And between them, since we are "vintage" collectors, I would choose 6536/1.