I've always wondered about this too, just how many different brands the cal.11 and derivatives was used in. Like finding a diamond in the rough I guess I willingly follow my wife to otherwise painfully boring antique shows in hope of finding a Dugena Siffert at the bottom of a vendors display case for $25.

To take this one step further, of all these brands' models which ones were case sizes around 42mm? The reason I ask is because I've come to the conclusion that I must be very size sensitive, I find even 40mm cases too small for me and 43+mm just too big. I've had some great watches that were 37mm, 39mm and no matter how beautiful they were I just couldn't bond with them. So now I look at only vintage chronos, and only around 42mm is size.