On the top left of my Poser 4 screen is a row of icons including one for "chain break"? What does it do? What is it for? How to use it? I have been making a Poser model of a UK-made type of industrial and diving oxygen rebreather set called a Salvus (made by Siebe Gorman). It has a long breathing tube that runs from a kit pack at the left waist to a breathing mask. It has 15 segments, 0 to 12, and of those 1 to 12 are an IK chain, and 1 to 11 are curve. I know how to long to make it, as I have measured a real one. In Poser I run into two snags with it:- (1) Sometimes Poser routes it so it goes through the flesh of the man's left arm and so I need to reroute it a bit without the job being like wrestling with an angry python. Can I use "chain break" here? (In reality the man's arm would push it aside a bit.) (2) In some positions of his head, the end pulls of the mask because it won't quite reach. In reality the tube, being rubber, stretches a bit. I would like to be able to tell Poser that, it such and such an IK chain can't reach whatever its goal is inkyParented to, scale all the chain members a bit along the direction of the chain. (I suppose I could slave all the segments' yScale's to one master parameter dial "lengthen breathing tube", but there is a bug that often makes slaved morphs obey the right named master in the right named part in a wrong model, because the slaving mechanism doesn't keep track of models being renamed on loading when there is already a model on stage with the same name, and I may want to put two divers with Salvuses in the same scene.)