Placement tools follow the rules set by AutoFittingOptions.xml. Similarly, the manipulation tools Join and Device Hookup behavior uses auto placement to complete their functionality. The HVAC join tool automatically places elbows and takeoffs, and the plumbing join tool places elbows and tees depending upon the nature of the joint. Device Hookup uses automatic placement by routing between devices with combinations of fittings, duct, pipe, flex duct and flexible pipe.