The IWC GST Automatic Alarm

By Michael Disher



This is the titanium IWC GST Automatic Alarm, ref. 3537/9269. “GST” stands for Gold, Steel and Titanium, the three metals in which this line of watches is available. The GST line also includes an automatic chronograph, the Aquatimer and the Deep One.


The Movement

The Automatic Alarm features a nicely finished and decorated Cal. 917, based on the JLC Cal. 916. This handmade automatic movement with 220 parts and 22 rubies is 30 mm in diameter and 7.45 mm thick. Tuned to 28, 800 vibrations per hour, this movement has a power reserve of 44 hours. The movement is shock resistant and anti-magnetic. The seconds do not hack, and the date is not quickset.

The alarm mechanism consists of a hammer that vibrates rapidly, striking a pin that makes contact with the small protrusion in the center of the inside of the case back, so the wearer feels the alarm as a slight vibration. The alarm is wound and set via the upper crown. The small red-tipped hand indicates the time for which the alarm is set. The alarm is fairly loud, though I would not be confident it would wake me in the morning. On the other hand, were it to sound during a business meeting, everyone would hear it. The alarm buzzes; the sound reminds me of a large insect flying by. At full wind, the alarm lasts approximately 15 seconds. Less wind yields a shorter alarm. I had some difficulty getting the alarm to sound when set for a short time in the future. If you need to remind yourself to do something in 5 or 10 minutes, use a post-it.

The Case and Bracelet

This Automatic Alarm’s case and bracelet are titanium, which means they are extremely light and not as “cold” as steel, though the metal’s color may not appeal to everyone. On my somewhat crude scale, the Automatic Alarm weighed in at about 115 grams. The case measures 39.7 mm in diameter not including the crowns, and 13.25 mm thick. The instruction manual pegs water resistance at 30 meters. The caseback is also titanium, which may be necessary to create the vibrating alarm effect, but which also hides a very attractive movement. The crystal is sapphire, slightly domed, and does not appear to be anti-reflective coated. The lower crown, which effects manual winding of the watch, plus date and time setting, screws down. The upper crown, which winds and sets the alarm, does not screw down.

The bracelet is one of the more remarkable elements of this watch. It is patented, and made with tolerances of .005 mm. The bracelet’s integration into the case is smooth and very pleasing to the eye. Links are added or removed by means of spring loaded buttons on the underside of each center link. These buttons hold in place the pins that join the links. Depressing a button allows the corresponding pin to be removed. This system is a clear improvement on screwed in pins, which often work their way loose over time. The clasp works extremely well, and feels very precise. Overall, the case and bracelet are exceptionally well finished. The only shortcoming I could detect in the bracelet is occasional tugs at the hairs on my arm. Perhaps the links should be set a wee bit further apart.

In the scan above, the link pin release buttons can be seen in the middle of the center links.


In the scan above left, the protrusion from the center of the inside of the case back transmits the vibration from the alarm to the wearer’s wrist.

The Dial and Hands

The dial and hands are very well executed, with tritium markers and tritium coated hour, minute and second hands. The alarm hand is red-tipped, but has no tritium, which means you can’t set or check the time the alarm is set for in the dark.


The GST Automatic Alarm comes in an attractive black leather box, and a tool is provided to adjust the bracelet (though no special tool is required). The instruction manual is informative and complete.

Other Versions and Prices

The model reviewed here lists at $4995. The list price in steel is $5195, and in 18K yellow gold, the list price is $19,500.


© 2000 Michael J. Disher