In 1936 Charvin introduced the Charvin GRI-GRI Route, a direct-pull development of the pull-chain 1953 Charvin Le Lautaret. In 1937 Charvin, confusingly, renamed this model as the Charvin Le Lautaret.

It was a fairly well made, simple, mechanism with a distinctively offset pulley cage. The sliding rod and the spring that controlled the movement in and out were both reasonably well sealed. This was probably quite a good design for maintaining a reasonably constant chain gap.

This particular example has a silver pulley cage, silver 35.0mm diameter pulleys, 10mm pulley bot nuts, a cable adjuster and a curved tube to direct the cable.

• Derailleur brands: Charvin
• Country: France
• Date of introduction: 1937?
• Date of this example: unknown
• Model no.: unknown
• Weight: 302g excluding, chainstay clamp bolt, cable clamp bolt, spring and chainstay spring clip
• Maximum cog: 28 teeth
• Total capacity: 28 teeth?
• Pulley centre to centre: 76mm
• Index compatibility: friction
• Chain width: 1/8”
• Logic: low normal
• B pivot: none
• P pivot: sprung
• Materials: steel with a brass (?) cable clamp