Italo Fontana has very well figured out how to design big watches. U-Boat watches are between 45mm and 55mm in diameter and even reach 65mm in the particular case of the U-1942. One thing that has not been associated much with these gargantuan timepieces, however, are complications. Showing that they are at the height of more traditional watchmakers to produced complicated watches, U-Boat released the U-51 Rattrappante complicated model.

With a complex system of levers, springs, and pinions, the “rattrapante” or split-second chronograph movement is one of horology’s finest mechanisms. Its function is to allow the user to mark a time measurement without stopping the ongoing timer. This is done by overlapping two independent seconds hands. After starting the chronograph as usual, a third chronograph pusher can be used to stop one of the overlapping second hands and allow the user to take a reading. This can be used for timing lap times for instance. The English name for this type of chronograph is derived from the action of splitting the hands. Once the button is pushed again the hand that had stopped catches up to the primary chronograph seconds hand instantly. This gives the function its French name: rattrapante.

Mostly you will find such fine mechanisms in more traditional and elegant watches, but the U-51 is nothing like these. The colossal case is 51mm in diameter without counting the impressive crown cap and pushers. It is undeniably based on military styling with a protruding, protective bezel, five visible fastening screws, and a matte satin finish. Although the exact measurement is not known yet, the thickness of the case is evident. The screw-locking crown protector ?��Ǩ��� on the left as always with U-Boat watches ?��Ǩ��� has been greatly reworked from the company’s more basic models. So have the hinge system that secures the crown cover to the case and the start/stop pushers. A final, subtle touch of style is created by abandoning the lugs, making the strap seem integrated with the case.

What makes the U-Boat U-51 Rattrapante special is that every part of it has been amplified. Even the strap has been adorned with the most extravagant alligator leather and fortified with a rubber border. All these extras earn the U-51 a price tag of roughly US$15,000, which places the watch amongst the most expensive stainless steel U-Boats, but it is also amongst the rarest. The U-51 will be produced in very limited quantities and is in its own category amongst the U-Boat watch collection.

Written by Marco Gagliano. Marco is a specialist of U-Boat watches at Matt Baily.