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

Remarks:

• 21 and 1721 are probably different names for the same movement. Most movement catalogs list it as caliber 1721

• Listing ID: 17899
• Manufacturer / Brand: Langendorf / Lanco
• Caliber: 21 / 1721
• Size in French Lignes: 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: 15
• Setting Lever Screw/Pin Position: Left
• Balance Position: Right (0 - 120°)
• Holes in setting lever spring or rocking bar: 4
• Shock Protection: None
• Beats per hour: 18,000
• Balance Type: Monometallic screw balance
• Power Reserve: Unknown
• Production Period: Unknown, probably around 1949
• Country: Switzerland
• Identification: Movement marked with LANCO. Listed in the Jacob catalog from 1949 and several other catalogs.
• Contributor ©: Uhrforum.de member buchenhain
• External Link: https://uhrforum.de/threads/identifizierte-uhrwerke-die-weder-bei-ranfft-lorenz-noch-im-watch-wiki-zu-finden-sind.86322/page-76#post-10473149