17 1/2”’ | Hand Wind | Swiss Lever | Small Seconds |

Remarks:

• Also known internally by Omega as Cal. 68a
• S in the caliber designation stands for Savonnette (hunter movement)
• The movement is also available as a Lépine (hunter) version 39.5 L (68) and with 17 and 21 jewels

• Listing ID: 3476
• Manufacturer / Brand: Omega
• Caliber: 39,5 S
• Size in French Lignes: 39,5 mm (17 1/2''')
• 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: Right
• Balance Position: Bottom (120 - 240°)
• Shock Protection: None
• Beats per hour: 18,000
• Balance Type: Bimetallic screw balance
• Power Reserve: Unknown
• Production Period: 1917 - 1928
• Identification: Wheel train bridge marked with Omega. Marked 39.5 S on the plate next to the balance wheel.
• External Link: https://uhrforum.de/threads/identifizierte-uhrwerke-die-weder-bei-ranfft-lorenz-noch-im-watch-wiki-zu-finden-sind.86322/page-24#post-3480524
• Country: Switzerland
• Contributor ©: Uhrforum.de member Badener (Andreas Kelz)