see also UK patent # 601,743

1. Date: UK application 1945
   

2. Derailleur brands: Constrictor, Osgear
   

3. Derailleurs: Constrictor
   

see also UK patent # 601,744

1. Date: UK application 1945
   

2. Derailleur brands: Constrictor, Osgear
   

3. Derailleurs: Constrictor prototype
   

Constrictor Derailleur - instructions

1. Date: 1946
   

2. Derailleur brands: Constrictor, Osgear
   

3. Derailleurs: Constrictor
   

see also Holdsworth - Aids to Happy Cycling

1. Date: 1949
   

2. Derailleur brands: Constrictor, Cyclo Gear Company, GB, Huret, Osgear, Resilion, Simplex, TriVelox
   

3. Derailleurs: too many to mention