Used Hytrol 4A 40:1 Ratio Gear Reducer input shaft is about 3/4" dia. output shaft dia. 1" 

Ratio 40:1

 Used Gear reducer it is off the shelf from a closed factory that kept spares for their equipment. 

[Please Look at all the pictures they are part of the description]

                                                                                         [B1-F1-R2-S4-1]