13 1/2”’ (30.4 mm) | Height 7.4 mm | Automatic | Swiss Lever | Small Seconds | Retrograde Date/Day |

Remarks:

• Automatic (unidirectional winding), small seconds at 9 o’clock (hacking), retrograde date at 9:30 o’clock (quick adjustment via pusher at 8 o’clock), retrograde weekday at 2:30 o’clock (quick adjustment via pusher at 4 o’clock)
• The ST2551 is a member of a very large ST25/TY25 movement family
• Movement with perlage
• Ball bearing rotor

• Listing ID: 159
• Manufacturer / Brand: Sea-Gull
• Caliber: ST2504 / TY2504
• Size in French Lignes: 13 1/2'''
• Size range mm largest diameter: 22 - 31 mm
• Shape: Round
• Winding: Automatic
• Hands Setting: Crown
• Seconds Hand: Small seconds
• Escapement: Lever (Swiss, English, Glashütte)
• Date, Day, Month...: Date & Day
• Jewels: 33
• Setting Lever Screw/Pin Position: Right
• Balance Position: Left (240 - 360°)
• Shock Protection: Similar to Incabloc
• Beats per hour: 21,600
• Balance Type: Glucydur
• Power Reserve: Approx. 45 hours
• Production Period: Presumably at least since 2008
• Identification: Movement listed on the Sea-Gull website
• External Link: https://uhrforum.de/threads/identifizierte-uhrwerke-die-weder-bei-ranfft-lorenz-noch-im-watch-wiki-zu-finden-sind.86322/page-60#post-8551029
• Country: China
• Contributor ©: Uhrforum.de member Badener (Andreas Kelz)