6 3/4 x 11”’ | Hand Wind | Swiss Lever | No Seconds |

Remarks:

• Technically identical movements with different bridge shapes:
  • AM 640
  • AM 642
  • AM 644
  • AM 651
  • AM 652

• Listing ID: 19356
• Manufacturer / Brand: AM / ZentRa
• Caliber: AM 651 = ZentRa 164
• Size in French Lignes: 6 3/4 x 11'''
• Size range mm largest diameter: 22 - 31 mm
• Shape: Form
• Winding: Manual (Crown)
• Hands Setting: Crown
• Seconds Hand: None
• Escapement: Lever (Swiss, English, Glashütte)
• Date, Day, Month...: None
• Jewels: 15
• Setting Lever Screw/Pin Position: Right
• Balance Position: Right (0 - 120°)
• Shock Protection: None
• Beats per hour: 18,000
• Balance Type: Monometallic screw balance
• Power Reserve: Unknown
• Production Period: Unknown, probably around 1928
• Country: Switzerland
• Identification: Dial side marked with AM, bridge side with ZentRa 164. As AM 651 listed in the Ebauches SA catalog from 1928.
• Contributor ©: Uhrforum.de member Badener (Andreas Kelz)