5 1/4 x 8 1/2”’ | Hand Wind | Swiss Lever | No Seconds |

Remarks:

• Variants of the movement:
  • Zenith 525: 18,000 bph, without shock protection
  • Zenith 528.8: 21,600 bph, without shock protection
  • Zenith 525.8-6: 21,600 bph, Incabloc shock protection

• Listing ID: 2126
• Manufacturer / Brand: Zenith
• Caliber: 525.8
• Size in French Lignes: 5 1/4 x 8 1/2''' (12.5 x 19.2 mm). The movement is more like 5 1/2''', but according to the manufacturer it is 5 1/4'''
• Size range mm largest diameter: 0 - 22 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: 21,600
• Balance Type: Monometallic screw balance
• Power Reserve: Unknown
• Production Period: 1946 - 1954 (57.000 pieces)
• Country: Switzerland
• Identification: Marked 525.8 under the balance. Original data sheet available.
• Contributor ©: Uhrforum.de member Badener (Andreas Kelz)
• External Link: https://uhrforum.de/threads/identifizierte-uhrwerke-die-weder-bei-ranfft-lorenz-noch-im-watch-wiki-zu-finden-sind.86322/page-42#post-5446433
• External Link 2: https://watch-movements.eu/blog/en/2020/10/03/zenith-movements-in-display-watch-cases/