17”’ | Hand Wind | Swiss Lever | Small Seconds |

Remarks:

• Caliber 73 = Lépine (open face), 74 = Savonnette (hunter)
• Swan-neck fine regulator
• Maltese cross stopwork on the mainspring barrel
• Dial feet are held by steel springs, no screws -> IWC patent CH55231

• Listing ID: 4860
• Manufacturer / Brand: IWC
• Caliber: 73 H4
• Size in French Lignes: 17'''
• Size range mm largest diameter: 31 - 40 mm
• Shape: Round
• Winding: Manual (Crown)
• Hands Setting: Crown
• Seconds Hand: Small seconds
• Escapement: Lever (Swiss, English, Glashütte)
• Date, Day, Month...: None
• Jewels: 16
• Setting Lever Screw/Pin Position: Left
• Balance Position: Right (0 - 120°)
• Shock Protection: None
• Beats per hour: 18,000
• Balance Type: Bimetallic screw balance with Breguet hairspring
• Power Reserve: Unknown
• Production Period: 1913 – 1930 (51.900 pieces)
• Identification: Listed in the Flume K1 catalog (part from 1957) and in the Engelkemper from 1966. Original documents from IWC available.
• External Link: https://uhrforum.de/threads/identifizierte-uhrwerke-die-weder-bei-ranfft-lorenz-noch-im-watch-wiki-zu-finden-sind.86322/page-4#post-1469319
• Country: Switzerland
• Contributor ©: Uhrforum.de member Badener (Andreas Kelz)