The IWC Mark XI was designed to meet the strict specifications of the British Ministry of Defence, which required a watch that was accurate, reliable, and easy to read in low-light conditions. The watch featured a black dial with luminous hands and hour markers, and was powered by an automatic movement, the IWC caliber 89.

Since these Mark XI watches were military issued, they were routinely sent in for service to keep them accurate, in good working order, and to keep up with ever changing regulations. As lume standards changed over the years, so did the Mark XI. Almost all original Mark XI dials were relumed as per the MoD. Around 1962, the same time most watch companies switched from radium to tritium luminescent material, the RAF required that there was a "T" in a circle on the dial to show that the lume was made of tritium.

Brand: IWC
Model: XI
Year: 1951
Case: Stainless steel
Size: 36mm
Lug to Lug: 46.5mm
Strap: Nato strap

CONDITION & SERVICING
-This IWC comes as watch only.
-The matte black dial is in very good condition.
- Hands and markers are showing an even patina. One hand is showing more wear than the other.
- The lume on the dial and on the hands has been relumed per the MoD specifications.
-There are a couple of marks on the side of the case, overall a really nice example. 
-Service history is unknown but is running to spec.