Spline stretch node allows you to create stretchy joint chain driven by an IK spline solver without creating additional nodes or expressions.
Since the node has global scale calculation feature you are able to use “Scale” attribute to make your rig scalable. The node does all calculation to keep the NURBS curve in correct scale and prevents any distortion might be caused by scaling.
Base on rigging requirements you need, this node can be connected to squash stretch or translate stretch node in order to get different type of stretch effects.