diff --git a/libsrc/csg/python_csg.cpp b/libsrc/csg/python_csg.cpp
index 41bb7376..83e33f5e 100644
--- a/libsrc/csg/python_csg.cpp
+++ b/libsrc/csg/python_csg.cpp
@@ -374,7 +374,8 @@ DLL_HEADER void ExportCSG(py::module &m)
                                    self.Save (filename);
                                  }))
     .def("Add",
-         [] (CSGeometry & self, shared_ptr<SPSolid> solid, py::list bcmod, double maxh)
+         [] (CSGeometry & self, shared_ptr<SPSolid> solid, py::list bcmod, double maxh,
+             py::tuple col)
           {
             solid->AddSurfaces (self);
             solid->GiveUpOwner();
@@ -384,6 +385,12 @@ DLL_HEADER void ExportCSG(py::module &m)
             self.GetTopLevelObject(tlonr)->SetTransparent(solid->IsTransparent());
             self.GetTopLevelObject(tlonr)->SetMaxH(maxh);
 
+            // cout << "rgb = " << py::len(rgb) << endl;
+            if (py::len(col)==3)
+              self.GetTopLevelObject(tlonr) -> SetRGB(py::cast<double>(col[0]),
+                                                      py::cast<double>(col[1]),
+                                                      py::cast<double>(col[2]));
+            
             // bcmod is list of tuples ( solid, bcnr )
             for (int i = 0; i < py::len(bcmod); i++)
               {
@@ -412,7 +419,8 @@ DLL_HEADER void ExportCSG(py::module &m)
               }
             return tlonr;
           },
-         py::arg("solid"), py::arg("bcmod")=py::list(), py::arg("maxh")=1e99
+         py::arg("solid"), py::arg("bcmod")=py::list(), py::arg("maxh")=1e99,
+         py::arg("col")=py::tuple()
          )
 
     .def("AddSurface", FunctionPointer
diff --git a/python/csg.py b/python/csg.py
index dff88d9b..6378c1c6 100644
--- a/python/csg.py
+++ b/python/csg.py
@@ -35,6 +35,6 @@ p3 = Plane(Pnt(0,0,0),Vec(0,-1,0)).bc("left")
 p4 = Plane(Pnt(1,1,1),Vec(0,1,0)).bc("right")
 p5 = Plane(Pnt(0,0,0),Vec(0,0,-1)).bc("bottom")
 p6 = Plane(Pnt(1,1,1),Vec(0,0,1)).bc("top")
-unit_cube.Add (p1*p2*p3*p4*p5*p6)
+unit_cube.Add (p1*p2*p3*p4*p5*p6, col=(0,0,1))
 # unit_cube.Add (OrthoBrick(Pnt(0,0,0), Pnt(1,1,1)))