A pipe in the Autodesk Revit MEP product. 
   Namespace:   Autodesk.Revit.DB.Plumbing  
  Assembly:   RevitAPI  (in RevitAPI.dll) Version: 2015.0.0.0 (2015.0.0.0) 
Syntax
Remarks
 The pipe is only available in the Autodesk Revit MEP product. 
 Inheritance Hierarchy
  System Object  
Autodesk.Revit.DB Element
Autodesk.Revit.DB HostObject
Autodesk.Revit.DB MEPCurve
Autodesk.Revit.DB.Plumbing Pipe
 
 Autodesk.Revit.DB Element
Autodesk.Revit.DB HostObject
Autodesk.Revit.DB MEPCurve
Autodesk.Revit.DB.Plumbing Pipe