A line set groups multiple connected segments into a single editable object, allowing designers to manipulate contours

https://wiki-wire.win/index.php/HVAC_Line_Set_Replacement_Warning_Signs_You_Shouldn%E2%80%99t_Ignore

A line set groups multiple connected segments into a single editable object, allowing designers to manipulate contours, outlines, and paths with consistent thickness, style, and snapping behavior across a project.