Revit 2012 based product key:
240D1 - Revit Architecture 2012
255D1 - Revit Structure 2012
297D1 - Revit MEP 2012
241D1 - AutoCAD Revit Architecture Suite 2012
256D1 - AutoCAD Revit Structure Suite 2012
257D1 - AutoCAD Revit MEP Suite 2012
765D1 - Autodesk Building Design Suite Premium 2012
766D1 - Autodesk Building Design Suite Ultimate 2012
For 2011 and 2010 version:
240C1 - Revit Architecture 2011
241C1 - AutoCAD Revit Architecture Suite 2011
595C1 - AutoCAD Revit Architecture Visualization Suite 2011
255C1 - Revit Structure 2011
256C1 - AutoCAD Revit Structure Suite 2011
297C1 - Revit MEP 2011
257C1 - AutoCAD Revit MEP Suite 2011
240B1 - Revit Architecture 2010
241B1 - AutoCAD Revit Architecture Suite 2010
595B1 - AutoCAD Revit Architecture Visualization Suite 2010
255B1 - Revit Structure 2010
256B1 - AutoCAD Revit Structure Suite 2010
297B1 - Revit MEP 2010
257B1 - AutoCAD Revit MEP Suite 2010