If you maintain a commercial or educational subscription entitlement, you can extract content packages natively: Revit 2017 Content Library - Forums, Autodesk

Always scan any downloaded .rfa or .exe file with antivirus software. Here are the top community-vetted sources:

Once downloaded, the content is typically an executable (.exe) file that extracts directly to your system. Revit 2017 Content Library - Forums, Autodesk