Set Scale Factor for converting texts and arrowheads: Choose one of the three options: This particularly applies to arrowheads, symbol line types and symbol fills. When opening a DXF/DWG file, you must define a scale at which you would like to see the correct ratios of elements drawn in AutoCAD. If no such original definition is available, or if you want to redefine it, use the pop-up list to choose either a standard drawing unit (1 meter, 1 millimeter, 1 inch, 1 foot) or a custom unit (any number of millimeters or inches).This checkbox means that ARCHICAD will use the Drawing Unit definition as set in the original imported DXF-DWG file. Prefer Drawing Unit definition in DXF/DWG file.Value of 1 DXF/DWG Drawing Unit in ARCHICAD: As you export or import something in DXF or DWG, you must set the size and distance conversion factor to ensure that ARCHICAD interprets the data correctly. This is an option of the DXF/DWG Translation Setup dialog box