This Ludoal has a main body that is copied from a 1950s pull-chain Simplex Tour de France , combined with a pulley cage that is derivative of a 1950s Campagnolo Gran Sport.

I believe that this is the original specification - the pulley cage looks identical to that of other Ludoals, but has a fixing that is specific to this model.

Finally, I should note that, although the pulley cage looks extremely similar to that of a Gambato, with the signature extra strut, the pulley cage length is 43mm, whereas all the relevant Gambatos have 45mm cages.

• Derailleur brands: Ludoal
• Country: Argentina
• Date of introduction: 1967?
• Date of this example: unknown
• Model no.: unknown
• Weight: 273g including hanger plate but excluding dropout bolt
• Maximum cog: 26 teeth (a guess)
• Total capacity: 18 teeth (another guess)
• Pulley centre to centre: 43mm
• Index compatibility: friction
• Chain width: 3/32”
• Logic: low normal
• B pivot: sprung
• P pivot: sprung
• Materials: largely steel, with bronze pulley cage plates