I need to know 

1.The Fabrication CAD MEP , Fabrication CAM Duct, Fabrication EST MEP are plug-ins with Revit and AutoCAD MEP?

And i know the fabrication is the separate software on AEC Collection.

pls answer any one about the above question.

Note and also i have an doubt here..

or If i purchase the Fabrication product separately ...those fabrication cad mep, est mep and cam duct are added as the PLUG IN on the REVIT AND AUTOCAD MEP environment?  Is it correct ??