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IWC Mark XI 6B/346 RAF British military steel

S$ 11,579

Available now

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Basic Info

Brand IWC
Ref. No. 6B/346
Movement Manual winding
Case material Steel
Bracelet material Textile
Year 1951
Condition 1 (mint)
Gender Men's watch/Unisex
Location United Kingdom, London
Price £6,500 (= S$ 11,579)
Availability Available now


Movement Manual winding
Movement/Caliber 89


Case material Steel
Case diameter 36 mm
Waterproof Not Waterproof
Material bezel Steel
Glass Plexiglass
Dial Black
Dial numerals Arabic numerals


Bracelet material Textile
Bracelet color Green
Clasp Buckle
Clasp material Steel


Center Seconds, Only Original Parts


This iconic, RAF issued IWC Mark XI (ref. 6B/346) in stainless steel is in fantastic vintage condition and has perfect mechanical functionality. It has recently been fully serviced, ensuring the watch is in full working order.

This IWC Mark XI is from 1950 and retains all of its military caseback engravings. The dial features the British military broad arrow and the circled ‘T’, implying that tritium was used for the luminous material. The original dial of the Mark XIs were lumed with radium, but sometime in the early 1960’s it was replaced by IWC with tritium as it was less radioactive and far safer. Many collectors do indeed prefer the look of the replaced ‘T’ dials compared to the radium ones.

Housed in a 36mm stainless steel case with fixed lugs, it has antimagnetic hands and an antimagnetic cage protecting the famous manual winding Cal. 89 movement, beating at 18,000 A/h.

The IWC Mark XIs were renowned for their timekeeping accuracy as this was a fundamental specification required by the British Armed Forces. As a result, these watches were regulated in five positions and tested in temperatures ranging from -5 degrees to 46 degrees over a 44 day testing period in order to meet the required standards.

Mark XIs were made for BOAC (British Overseas Airline Corporation), the RAF (Royal Air Force), the Royal Australian Air Force as well as other air forces and for civilians as well. The collectibility of this timepiece is largely underpinned by its historical significance as IWC’s entire modern Pilot range was inspired by the very Mark XI.

With pilot watches very much in demand today, due to their casual and utilitarian feel, this particular piece certainly fits the bill, especially with its wearable 36mm case and with both dial and case in exceptional unrestored condition. Specific to this example, it is from 1951 as shown by the caseback designation ‘/51’.

The luminous material matches the unrestored dial perfectly and has aged to a creamy yellow patina. The ’T’ on the dial, which was indeed added on by the British Military of Defence themselves when the dials were delivered by IWC, has faded slightly. This IWC Mark 11 comes with its correct engraved caseback, both on the outside and the inside (military Mark 11s were stamped ‘JWC’ on the inside of the caseback) and its ever important dust cover.
Our preowned watches have all undergone thorough mechanical inspections, including being ultrasonically cleaned, polished, resealed if appropriate and tested for at least four days, to ensure they meet our highest timekeeping standards.


All watches are either covered by a full, or a limited twelve month warranty. For example, due to their age, some vintage watches should not be subjected to the same conditions as when they were new. Please see our Terms & Conditions for further information.

If ordering from the UK before 1 PM, your watch will be sent by Royal Mail Special Delivery by Next Day. All of our parcels are fully insured.

If ordering from outside the UK, your watch will be dispatch the same day with DHL Global Express. Delivery is expected by the end of the next working day. However, delivery time may depend on customs clearance.

Viewings can be arranged in Central London by appointment.

You can cancel your order without giving any reason, within 14 days from the day the watch has been delivered to you.

For more information and photos, including 360° degree rotations at, please contact us.

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