IWC Ref. 2400 with original mesh bracelet, Cal. 403 manual-wind, serviced, circa 1973.

This is a manual-winding IWC model, Ref. 2400, produced in 1973.

The dial has aged from its original silver to a deep, champagne gold-like hue. The sunray finish creates a delicate sheen depending on the angle of light, allowing you to enjoy a one-of-a-kind appearance unique to an antique timepiece.
At the 12 o'clock position on the dial, the applied "IWC" logo, characteristic of this era, sits alongside the traditional "International Watch Co." signature in script, exuding the dignity of a vintage IWC.

The case is crafted from "STAYBRITE" steel, a mark of high-quality steel from that period. It is highly resistant to rust and conveys a deep, vintage luster to the present day.

It is powered by the manual-winding "Cal. 403," a movement renowned as a masterpiece.
The Cal. 403 features a thin design, with the thickness reduced to approximately 3.15mm compared to conventional movements. The design of the large, segmented bridge is beautiful, combining IWC’s robust watchmaking with aesthetic appeal.

The standout feature of this piece is its stylish design, which integrates a thin case with a mesh bracelet.
It features a free-adjust mechanism, eliminating the need for the "welded resizing" common in integrated bracelet models; you can easily adjust the size simply by sliding the buckle.
The lug-less design provides both a snug, seamless fit on the wrist and the functional beauty of a dress watch.

The crown is engraved with the "fish mark," a hallmark of IWC watches from that time.
With a diameter of approximately 4.6mm, the crown offers a good grip, allowing you to fully enjoy the tactile experience unique to a manual-winding model.

This is an excellent piece for those looking for a slim dress watch that won't get caught on shirt cuffs.

Condition

This watch has been overhauled and the exterior has been refinished.

While there are fine scratches on the crystal due to use, the visibility of the dial remains excellent.

The original mesh bracelet features a free-adjust design.
There is some distortion and wear from half a century of use, but it is within a range that can be enjoyed as vintage character. The connection between the watch case and the bracelet is more delicate than standard lug-and-spring-bar setups. As this is a valuable, irreplaceable bracelet, please handle it with care and avoid applying excessive pressure.

There are minute traces of corrosion around the outer edge of the case back due to age. This part is hidden while worn, and the price has been set with consideration for this condition.

To secure the bracelet, insert the 6 o'clock side into the buckle and snap it shut to lock.
We recommend operating it over a desk until you get used to it to prevent dropping the watch while putting it on. Also, to reduce the strain on the bracelet, please wear it with a little extra room around your wrist.

As this is a vintage timepiece, it is not water-resistant. Usage in environments with moisture (such as rainy days, washing your face, or hot days when you might sweat) is strictly prohibited.
Additionally, because it is a precision instrument, please be very careful to avoid strong impacts such as drops, and keep it away from magnetic fields (smartphones, PCs, speakers, magnets in bags, etc.).

Operation

Manual Winding: Rotate clockwise with the crown in the normal position.

Time Setting: Pull out the crown and rotate it clockwise.

How to Pull the Crown: Gently pull the crown out by inserting your fingernail between the case and the crown.

Pulling the crown too forcefully may cause it to come out, so please pull it out gently.
To prevent the crown stem from bending, always remove the watch from your wrist before operating it.