diff --git a/_setup/geometries/geometry.py b/_setup/geometries/geometry.py
index 5c5f3e74e4ff2003f9551c358be9c6d3a9150b2b..4a8a00af6af9a9c01c7d514c21ae62f0b9b5f377 100644
--- a/_setup/geometries/geometry.py
+++ b/_setup/geometries/geometry.py
@@ -236,7 +236,11 @@ class Geometry:
   
   def Save(self, filename):
     if not(self._mesh == None):
-      self._mesh.ngmesh.Save( filename )
+      ext = ".vol"
+      if(filename[-4:] == ext):
+        ext = ""
+      self._mesh.ngmesh.Save( filename + ext )
+
 # TOECDO
 #      if ( self.boundingBox.IsBoundingBox() ):
 #        tmp = filename.rfind("/")+1