Sinn 103 A Sa B pilot’s chronograph

This limited-edition pilot’s chronograph by Sinn is an addition to its 103 series of chronographs, and its major feature is the blue dial with sunburst decoration and silver subdials.

Case and dial

The stainless steel case is 41 mm in diameter and 17 mm thick, and it features the brand’s Ar-Dehumidifying Technology that extends watch functionality by reducing the amount of water vapour that enters the watch. The system is based on a small air-drying capsule filled with copper sulphate that absorbs moisture, diffusion-reducing seals, and a protective gas filling inside the watch. Together, these methods reduce the penetration of gaseous atmospheric water vapour into the watch, which in turn reduces the deterioration of lubricant oils and the onset of corrosion which increases wear and friction and would eventually make it necessary to service the watch. It also prevents fogging of the watch glass when it is transferred rapidly to a cool environment. The user can check the state of the copper sulphate capsule through a small window on the caseband, which gradually changes from light blue to deep blue as it absorbs moisture.


It is without doubt a tough watch, resistant to low pressure, external pressure up to 20 bars (200 metres water), and it is anti-magnetic.

The dial is clear and legible, with the chronograph seconds scale divided into quarter seconds, chronograph minutes and hours subdials at 12 o’clock and 6 o’clock respectively, continuous seconds at 9 o’clock, and day and date at 3 o’clock. The hour, minute and chronograph second hands have a coating in luminescent paint, and likewise the hour markers and the triangular zero marker on the bezel.


The watch has a screw-down crown, which can be used for winding the watch, setting the time (with stop-time function for precise setting, and rapid date and day setting (rotating the crown clockwise sets the date, anticlockwise sets the day of the week). As for many watches, the date-setting function must not be used between 8 pm and 3 am.
The chronograph pushers are also screw-down. This feature makes using the chronograph a little more involved than watches without screw-down pushers, but they help it attain the excellent water resistance certified by the DIN 8310 standard.

The pilot’s bezel is a countdown bezel, so that you rotate the bezel until the number of minutes to be timed is opposite the minute hand. At any time, you can see the number of minutes remaining.



The movement is the self-winding ETA Valjoux 7750, running at 4 Hertz (28,800 vph), power reserve 42 hours. It uses the coulisse-lever system for controlling chronograph operation, simpler and cheaper to manufacture than the column wheel system. The oscillating weight is decorated with the Sinn logo, and the movement also features blued screws and machine-turned bridges.


Changeable strap

The watch has a blue leather strap with embossed alligator pattern and white stitching. The presentation box also includes a grey textile strap that the user can change as required. This is a nice feature as it extends the life of the leather strap, by using the textile strap (for example) in summer or on rainy days.

Reference and price

The Sinn 103 A Sa B pilot’s chronograph, reference 103.0601, is a limited edition of 500 units. It is supplied with a three-year guarantee, and the box includes both the blue leather strap and a second textile strap. Price is €1,990. The watch can be purchased on the company website, delivery time 8 weeks.
Below, version with blue alligator strap:
Below, movement detail:


Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.