IWC Schaffhausen · ref Mark XI (6B/346) · 1948–early 1980s
The Mark XI is the watch that made IWC's name for pilot's watches. It entered RAF and Fleet Air Arm service around 1948–49 to help navigators with dead reckoning, and the Royal Australian Air Force took it up in 1950. Inside is the hand-wound cal. 89, a 17-jewel movement at 18,000 beats an hour, wrapped in a soft-iron inner case that shields it from magnetism. The case is 36mm, with a black dial, white Arabic numerals and a triangle at 12. The RAF bought some from Jaeger-LeCoultre at first, then took only IWC watches through 1953, and it didn't officially retire the type until 1981. Issued watches carry a broad arrow, the 6B/346 code and an issue number on the back. Many got new tritium dials in service, marked with a small T in a circle above 6, which tells you the radium original is gone. IWC kept making the Mark 11 into the early 1980s.
The caliber
The cal. 89 is the hand-wound IWC movement behind the Mark XI, a 17-jewel caliber at 18,000 beats an hour with a Breguet hairspring and IWC's own drive for the central seconds hand. Dealers still call it one of the most robust three-hand movements ever made. On this watch the value story is less about the caliber and more about what surrounds it, from the issue markings on the back to whether the dial is the first one or a later tritium replacement.
Some original dials and hands on the IWC Mark XI carry radium paint, which stays radioactive long after the glow fades. Worn with the case closed it’s generally considered low risk. The real hazard is dust from flaking paint, so leave the case shut, don’t scrape or touch the dial, and have a watchmaker who handles radium do any service.
More in our radium and tritium guide.
The dial is the big question, since many were replaced in service and others have been refinished since. Casebacks were swapped too, so make sure the markings and the dial tell the same story.
Buying guide
Only two Mark XIs are for sale, both from Germany at $7,730 and $9,027 delivered, so the band is just those two asks. We'd start with the one titled original and tested at $7,730, and ask both sellers for a caseback photo showing the broad arrow, 6B/346 and an issue number, plus a dial photo to check for a T in a circle above 6, which marks a tritium service dial. Budget for possible import duty, and check each seller's feedback and return policy on the item page, since eBay's watch search doesn't show them.
$7,729.93est. delivered
The lower of the two asks at $7,730 delivered from Germany, titled original and tested. Original is the seller's word, so check that the dial and caseback markings tell the same story.
IWC Mark XI, Original, Estate, Tested
Delivered prices include shipping as eBay quoted it to a US address on Oct 6, 2026. Many sellers charge by distance, so your total may differ. eBay shows yours before you pay.
Snapshot
Checked . Some may have sold.
Delivered prices include shipping as eBay quoted it to a US address on Oct 6, 2026. Many sellers charge by distance, so your total may differ. eBay shows yours before you pay.
Used$7,729.93est. delivered
$7,653.40 + $76.53 shipping
Buy It Now$7,653.40
This seller takes offers, and many sellers accept less than the asking price.
Fine if you might miss it? Send an offer first. Someone else can still buy it while you wait for a reply.
Want it for sure? Use Buy It Now.
Good buy
Titled original, estate and tested. Ships from Germany.
Seller: Seller on eBay
Check feedback on the listing
Used$9,026.52est. delivered
$8,992.75 + $33.77 shipping
Buy It Now$8,992.75
This seller takes offers, and many sellers accept less than the asking price.
Fine if you might miss it? Send an offer first. Someone else can still buy it while you wait for a reply.
Want it for sure? Use Buy It Now.
Our take
Titled broad arrow with the cal. 89. Ships from Germany.
Seller: Seller on eBay
Check feedback on the listing
Prices change daily. The live eBay search shows everything listed now, including anything new since Oct 6, 2026.
See every listing on eBay ↗eBay searchA fresh strap, a set of spring bars and a spring-bar tool are the cheap part of making an old IWC Mark XI wearable again. This searches Amazon for the usual kit.
Search straps & tools ↗Amazon search
IWC Schaffhausen · Ingenieur
Dressref 666A / 666AD
$3,525–$5,050 typical ask
Zenith · Cairelli
Chronographref Cronometro Tipo CP-2
$14,575–$18,200 typical ask
IWC Schaffhausen · Portugieser
Dressref 325
$18,000–$18,025 typical ask
Longines · 13ZN chronograph
Chronographref 13ZN
$7,350–$19,150 typical ask