They were a decade marked not only by advances in technology
For a look at Topper's original announcement for the model
On a 78350/557 Oyster bracelet
Their Tributes to the Polaris
the Loga only ran for a short time and did not enjoy the success of the Chronomat
Patek Philippe Perpetual Calendar 'Tiffany' Storage They were a decade markedA perpetual calendar is like a small computer on your wrist. Think of it this way: Imagine a watch that keeps track of not only the time, but also the date, the day of the week, and the month, and also tells you whether its a leap year or not, and what the current phase of the moon is. Oh, and one more thing imagine it does all of this mechanically, using springs and gears, and that you only have to adjust it once every century or so. Crazy, right?