From the Autodesk App Store:
This Autodesk® Revit® add-in allows you to make use of a CTB file to transform your CAD drawing before importing it.
Usually the CAD drawings are drawn in lines of different color/thickness than what they’re supposed to be plotted. Thus before importing in Revit you need to have this extra step of transformation.
CTB Link does just that. Give it a CTB file, a CAD file and you will have your drawing in Revit just as you’d plot the CAD file in a PDF or printer.