Derailleur shims for adapting front derailleur clamps to a different sized frame seat tube.
- Derailleur = the size of the clamp on the front derailleur you have
- Frame = the size of the seat tube the derailleur plus shim will fit
- Front Derailleur Clamp: 25.4 (1")
- Front Derailleur Clamp: 28.6 (1-1/8")