diff --git a/Cassiopee/CPlot/apps/tkCADFix.py b/Cassiopee/CPlot/apps/tkCADFix.py
index c49f0f596..72054bc67 100644
--- a/Cassiopee/CPlot/apps/tkCADFix.py
+++ b/Cassiopee/CPlot/apps/tkCADFix.py
@@ -384,6 +384,7 @@ def trimFaces(event=None):
 
 #==============================================================================
 def checkWatertight(event=None):
+    import OCC.PyTree as OCC
     if CTK.t == []: return
     b = Internal.getNodeFromName1(CTK.t, 'FACES')
     if b is None:
@@ -416,19 +417,18 @@ def checkWatertight(event=None):
     p = Internal.getNodeFromName1(CTK.t, 'LEAKS')
     gnob = C.getNobOfBase(p, CTK.t)
 
-    f = Internal.getZones(b)
-    f = G.zip(f, tol)
-    f = T.join(f)
-    #f = G.close(f, tol)
-    ef = T.splitConnexity(f)
+    ef = OCC.getComponents(CTK.t, tol)
+
     VARS[6].set('Components: %d'%(len(ef)))
 
     isWatertight = False
     try:
-        ext = P.exteriorFaces(f)
-        ext = T.splitConnexity(ext)
-        for i in ext: CTK.add(CTK.t, gnob, -1, i)
-        if len(ext) == 0: isWatertight = True
+        isWatertight = True
+        for f in ef:
+            ext = P.exteriorFaces(f)
+            ext = T.splitConnexity(ext)
+            for i in ext: CTK.add(CTK.t, gnob, -1, i)
+            if len(ext) != 0: isWatertight = False
     except: isWatertight = True
 
     (CTK.Nb, CTK.Nz) = CPlot.updateCPlotNumbering(CTK.t)
diff --git a/Cassiopee/CPlot/apps/tkTree.py b/Cassiopee/CPlot/apps/tkTree.py
index d9d50a3e4..d3160c892 100644
--- a/Cassiopee/CPlot/apps/tkTree.py
+++ b/Cassiopee/CPlot/apps/tkTree.py
@@ -903,7 +903,7 @@ def PVT_displayNode(self, clear=False):
                 for z in zones:
                     base, c = Internal.getParentOfNode(CTK.t, z)
                     #noz = CPlot.getCPlotNumber(CTK.t, base[0], z[0])
-                    noz = dnz[base[0], z[0]]
+                    noz = dnz[base[0]][z[0]]
                     selected.append((noz, s))
                 if clear: CPlot.unselectAllZones()
                 CPlot.setSelectedZones(selected)
diff --git a/Cassiopee/OCC/OCC/Atomic/identifyTags.cpp b/Cassiopee/OCC/OCC/Atomic/identifyTags.cpp
new file mode 100644
index 000000000..c43c6dbcc
--- /dev/null
+++ b/Cassiopee/OCC/OCC/Atomic/identifyTags.cpp
@@ -0,0 +1,75 @@
+/*    
+    Copyright 2013-2024 Onera.
+
+    This file is part of Cassiopee.
+
+    Cassiopee is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    Cassiopee is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with Cassiopee.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "occ.h"
+#include <map>
+
+// ============================================================================
+/* Identify int in __tag__ array */
+// ============================================================================
+PyObject* K_OCC::identifyTags(PyObject* self, PyObject* args)
+{
+  PyObject* array;
+  if (!PYPARSETUPLE_(args, O_, &array)) return NULL;
+
+  // Check array
+  E_Int nil, njl, nkl;
+  FldArrayF* f; FldArrayI* cn;
+  char* varString; char* eltType;
+  E_Int res;
+  res = K_ARRAY::getFromArray3(array, varString, f, nil, njl, nkl, 
+                               cn, eltType); 
+  
+  if (res != 1 && res != 2)
+  {
+    PyErr_SetString(PyExc_TypeError,
+                    "identifyTags: invalid array.");
+    return NULL;
+  }
+
+  E_Int post = K_ARRAY::isNamePresent(varString, "__tag__");
+  if (post < 0)
+  {
+    RELEASESHAREDB(res, array, f, cn);
+    PyErr_SetString(PyExc_TypeError,
+                    "identifyTags: __tag__ not found.");
+    return NULL;
+  }
+  post++;
+  E_Float* ft = f->begin(post);
+
+  std::map<E_Int, E_Int> kmap;
+  E_Int n = f->getSize();
+  E_Int val;
+  for (E_Int i = 0; i < n; i++)
+  {
+    val = round(ft[i]);
+    kmap[val] = 1;
+  }
+
+  // Export a list
+  PyObject* l = PyList_New(0);
+  for (const auto& pair : kmap) 
+  {
+    PyObject* o = PyLong_FromLong(pair.first);
+    PyList_Append(l, o);
+  }
+  RELEASESHAREDB(res, array, f, cn);
+  return l;
+}
\ No newline at end of file
diff --git a/Cassiopee/OCC/OCC/OCC.py b/Cassiopee/OCC/OCC/OCC.py
index be2606f04..48ae4372b 100644
--- a/Cassiopee/OCC/OCC/OCC.py
+++ b/Cassiopee/OCC/OCC/OCC.py
@@ -14,7 +14,8 @@
 __all__ = ['convertCAD2Arrays', 'switch2UV', 'switch2UV2', '_scaleUV', '_unscaleUV',
            'meshSTRUCT', 'meshSTRUCT__', 'meshTRI', 'meshTRI__', 'meshTRIU__',
            'meshTRIHO', 'meshQUAD', 'meshQUAD__', 'meshQUADHO', 'meshQUADHO__',
-           'ultimate', 'meshAllEdges', 'meshAllFacesTri', 'meshAllFacesStruct']
+           'ultimate', 'meshAllEdges', 'meshAllFacesTri', 'meshAllFacesStruct',
+           'identifyTags__']
 
 # algo=0: mailleur open cascade (chordal_error)
 # algo=1: algorithme T3mesher (h, chordal_error, growth_ratio)
@@ -734,3 +735,7 @@ def getNbFaces(hook):
 # Return the file and format used to load CAD in hook
 def getFileAndFormat(hook):
     return occ.getFileAndFormat(hook)
+
+# identify tag component
+def identifyTags__(a):
+    return occ.identifyTags(a)
\ No newline at end of file
diff --git a/Cassiopee/OCC/OCC/PyTree.py b/Cassiopee/OCC/OCC/PyTree.py
index 3a48a9168..c3fa11ba1 100644
--- a/Cassiopee/OCC/OCC/PyTree.py
+++ b/Cassiopee/OCC/OCC/PyTree.py
@@ -1376,4 +1376,43 @@ def _updateTree(t, oldNbEdges, oldNbFaces, new2OldEdgeMap, new2OldFaceMap):
 
     # recolor
     _setLonelyEdgesColor(t)
-    return None
\ No newline at end of file
+    return None
+
+def identifyTags__(a):
+    array = C.getFields(Internal.__FlowSolutionNodes__, a, "__tag__", api=3)[0]
+    return OCC.identifyTags__(array)
+
+def getComponents(t, tol=1.e-10):
+    """Return the number of components in t, taggings faces with component number."""
+    import Transform.PyTree as T
+    # init FACES with a tag
+    FACES = Internal.getNodeFromName1(t, 'FACES')
+    zones = Internal.getZones(FACES)
+    for z in zones:
+        # Get face number
+        CAD = Internal.getNodeFromName1(z, 'CAD')
+        no = Internal.getNodeFromName1(CAD, 'no')
+        no = Internal.getValue(no)
+        # init tag
+        C._initVars(z, '__tag__ = %d'%no)
+
+    # join all zones
+    a = G.zip(zones, tol)
+    a = T.join(zones)
+    a = T.splitConnexity(a)
+
+    # Identify faces in component
+    tags = {}
+    for c, z in enumerate(a):
+        tags[c] = identifyTags__(z)
+    
+    # Get the component number for each zone
+    pos = getAllPos(t)
+    for k in tags:
+        C._addFamily2Base(FACES, 'Component%02d'%k)
+        faces = tags[k]
+        for f in faces:
+            z = getFace(t, pos, f)
+            C._tagWithFamily(z, 'Component%02d'%k)
+
+    return a
\ No newline at end of file
diff --git a/Cassiopee/OCC/OCC/occ.cpp b/Cassiopee/OCC/OCC/occ.cpp
index 6bc988ced..acfd713ef 100644
--- a/Cassiopee/OCC/OCC/occ.cpp
+++ b/Cassiopee/OCC/OCC/occ.cpp
@@ -87,6 +87,7 @@ static PyMethodDef Pyocc [] =
   {"rotate", K_OCC::rotate, METH_VARARGS},
 
   {"getOppData", K_OCC::getOppData, METH_VARARGS},
+  {"identifyTags", K_OCC::identifyTags, METH_VARARGS},
 
   {NULL, NULL}
 };
diff --git a/Cassiopee/OCC/OCC/occ.h b/Cassiopee/OCC/OCC/occ.h
index 77d90bf06..1b4c233ae 100644
--- a/Cassiopee/OCC/OCC/occ.h
+++ b/Cassiopee/OCC/OCC/occ.h
@@ -86,7 +86,7 @@ namespace K_OCC
   PyObject* rotate(PyObject* self, PyObject* args);
 
   PyObject* getOppData(PyObject* self, PyObject* args);
-
+  PyObject* identifyTags(PyObject* self, PyObject* args);
 }
 
 #endif
diff --git a/Cassiopee/OCC/srcs.py b/Cassiopee/OCC/srcs.py
index f3184826e..bf64c3627 100644
--- a/Cassiopee/OCC/srcs.py
+++ b/Cassiopee/OCC/srcs.py
@@ -73,7 +73,8 @@ def getFiles(module):
         'OCC/Atomic/scale.cpp',
         'OCC/Atomic/rotate.cpp',
 
-        'OCC/Atomic/getOppData.cpp']
+        'OCC/Atomic/getOppData.cpp',
+        'OCC/Atomic/identifyTags.cpp']
 
 import KCore.Dist as Dist