Baumuster A Dial
Big Pilot B-Uhr / Grosse Fliegeruhr 431 — Baumuster A Dial
IWC made only the Type A layout: white Arabic hours on black with a large triangle and two dots at 12, sword hands and a long white seconds hand. Known cases are numbered alongside the FL 23883 marking, e.g. 1033449, sold in October 1940.
About 1,000 pieces.
Identifying details
- Military issue
Issued to armed forces.
- Baumuster A dial
B-Uhr layout with Arabic hours and a triangle flanked by two dots at 12.
- FL 23883 marking
Luftwaffe requisition marking “Anforderz. FL 23883” engraved on B-Uhr cases.
- Soft-iron inner case
Soft-iron inner case and dial forming a cage that shields the movement from magnetic fields.
Variants of 431
Reference overview →| Variant | Production |
|---|---|
| Baumuster A DialCurrent | 1940 |
Case & movement
- Reference
- 431
- Production
- 1940
- Case diameter
- 55 mm
- Movement
- Manual winding
- Date
- No
- Caliber
- IWC 52 T.S.C.
Dial, bezel & hands
- Dial colour
- Black
- Hands
- Sword
Movement
IWC 52 T.S.C.
Final military version of IWC’s long-running 19-ligne calibre 52 pocket-watch movement, converted to indirect centre seconds with a stop function. A last batch of 1,200 was made in 1940 for the ref. 431 and for British Navy deck watches.