Last week, Parmigiani Fleurier impressed us with their novel take on the GMT with the Tonda GMT Rattrapante, offering a second, independently adjustable hour hand on demand. But that wasn?t the only thing we saw during Watches & Wonders, a pair of openworked Tonda PF references joined the fun and may have been the most surprising watches of the entire show. The Tonda PF is a slim platform that is showing its range with these new models, something we saw the potential for after getting a hands-on look at the base model right here.

The GMT Rattrapante as a concept (which we wrote about here) is an idea so simple and effective that it?s difficult to believe that this is the first time it?s been done. The manner in which it has been implemented retains the full charm and simplicity of the time and date, only better because it nixes the date aperture at 6 o?clock, so you get more of that texture pattern. That does mean no numerals, no am/pm indication, or really anything other than the hour markers with which to make use of, so while legibility isn?t on the level of a typical GMT tool watch, there?s enough there to make some practical use of.
On the wrist, the GMT is as compelling as the Tonda PF, despite moving from 7.9mm in thickness, to 10.7mm. Obviously, that still qualifies the watch as quite thin, but the key factor is the angle of the lug, and the integrated bracelet, which gets links that easily take any shape thanks to their pivot points. 

I had the opp...