Curve used to create an offset curve
To create an offset curve:
The NURBS object must contain at least one curve.
An offset curve is created.
If the parent curve is not linear, increasing the distance increasingly exaggerates the curvature of the offset curve.
The distance between the parent curve and the offset curve, in 3ds Max units.
This parameter is animatable.
The distance between the parent curve and the offset curve, in 3ds Max units.
Lets you replace the parent curve. Click the button, then click the curve to replace the original curve.