diff --git a/demo/PropertyGrid.py b/demo/PropertyGrid.py
index 3d9265e4..784b138e 100644
--- a/demo/PropertyGrid.py
+++ b/demo/PropertyGrid.py
@@ -678,7 +678,7 @@ class TestPanel( wx.Panel ):
                               wxpg.PG_TOOLBAR)
 
         # Show help as tooltips
-        pg.SetExtraStyle(wxpg.PG_EX_HELP_AS_TOOLTIPS)
+        pg.ExtraStyle |= wxpg.PG_EX_HELP_AS_TOOLTIPS
 
         pg.Bind( wxpg.EVT_PG_CHANGED, self.OnPropGridChange )
         pg.Bind( wxpg.EVT_PG_PAGE_CHANGED, self.OnPropGridPageChange )