The absence of backlash makes this parallel coupling a precision, low- cost replacement for gear or chain drives that can also rotate parallel shafts. Any number of shafts greater than two can be driven from any one of the shafts, provided two conditions are fulfilled:

1. All cranks must have the same length.

2. The two polygons formed by shafts centers on the moving and grounded frames must be identical.

The main disadvantage of this mechanism is its dynamic unbalance. The

moving frame should be made as light as possible. The mechanism can not be used for high speed.