Shawn Evjen submitted Duct Transition, an expert drafting utility that skillfully creates the transition element graphic between two different duct sizes given just a few selections. Load the LISP code and type Duct_Trans when you are ready to draw a transition section. First, select one edge of the existing duct (end point). Next, pick a point toward the opposite side (perpendicular to the ductrun direction). Last, enter the initial duct size (default is the distance between the two points just described) and the ending duct size. A transitional element (drawn using polylines on the current layer) is the automatic result.