Sinn 903 ST (Navitimer) Navigation Chronograph
For those that might be a little sniffy about the Breitling Navitimer then please keep in mind that Sinn are legally allowed to produce the watch with this dial layout and format having purchased the right when Breitling went bankrupt in the 1980s - and the case follows the form of the Navitimer 806 so the Sinn device is actually more of a true Navitimer than the current Breitling incarnation.
One of the most stunning features of this watch and one for which it is rightly famous is the dial which in addition to the fascinating variety of features goes through a multistage process which makes it one of the most difficult to produce, with over 30 separate steps involved. To ensure that it retains its rich contrast and colorfastness, it is galvanised with black nickel or silver nickel counters before the final milling which present the counters into the dial.
Thanks to the proven high grade automatic movement, the 903 remains both durable and reliable. In contrast to the classic Valjoux 7750 ebauchee design, the minute and second counters as well as the small second second counter are arranged 'tri-compax' style at 3, 6 and 9 o'clock. The date display is located at 4:30.
An eye-catching feature of the 903 is the additional crown at 10 o'clock. This is used to rotate the slide-rule ring around the outer edge of the dial. With this high-quality navigation chronograph upon which you can perform multiplication and division, calculate proportions and do various conversions - if you are clever enough!!
Now for a few details about this specific watch:-
- Sinn 903 ST w/- Valjoux 7750 (at the time this watch was made Sinn were using 'Top' grade Val. movements and adding a module for the compax dial layout. Sinn are now using the SW500 movement which is virtually identical to the Val. 7750)
- Original purchase date 2007
- Diameter: 41 mm (exc. crown)
- Lug width: 22 mm
- Height: 14.5 mm
- Domed sapphire crystal (no AR coating)
- Beautiful galvanised black dial
- WR 100m
- Internal bezel
- Secured for low pressure
The watch works, sets and winds perfectly showing an excellent 44 hour power reserve and the time keeping is approx. +1-3secs/day (measured face up, unworn). Chronograph is operating well and crisply resets. There are a couple of very minor strap changing marks on the lugs, and some very light marks on the case and bracelet but only commensurate with normal wear which are mentioned not as detractors but in the spirit of full disclosure.
The full package on offer includes : - the watch, bracelet (basically unused, w/- extra links, i.e. full length), original Sinn leather strap (used), boxes, and Sinn purchase/warranty card as pictured.
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