Creating technical documentation for any piece of hardware almost always requires that we work with AutoCAD or some other computer-aided design file type. We use Adobe Illustrator to manipulate this line art. There was a time when we could get the draftsperson to just send us a DWG or DXF file and we were good to go. We couldn't rotate or otherwise re-orient the image, of course, but for line art that's not usually necessary.
That's not the case any more: now, you have to specify the level of AutoCAD to save the file in. To open an AutoCAD file in Illustrator, the file has to be saved as AutoCAD 2007 or earlier. Which is kind of odd, given that just a few years ago (and well after AutoCAD 2007 was released in 2006), we never had to specify a revision level when asking for drafting files. They sent a DWG or DXF and we were in business.