see also US patent # 3,903,751

1. Inventor: Walter Dian
   

2. US application filed: April 1974
   

3. Derailleur brands: Excel
   

4. Derailleurs: Excel Dynamic
   

see also Boys’ Life - Sears advert

1. Date: June 1975
   

2. Derailleur brands: Excel
   

3. Derailleurs: Excel Dynamic Syncromesh (1st style)?, Excel Dynamic Syncromesh (2nd style)?
   

see also Boys’ Life - Sears advert (1st style)

1. Date: April 1976
   

2. Derailleur brands: Excel
   

3. Derailleurs: Excel Dynamic Syncromesh (1st style)?, Excel Dynamic Syncromesh (2nd style)?
   

see also Boys’ Life - Sears advert (2nd style)

1. Date: May 1976
   

2. Derailleur brands: Excel
   

3. Derailleurs: Excel Dynamic Syncromesh (1st style)?, Excel Dynamic Syncromesh (2nd style)?