diff --git a/src/main/java/org/gcube/portlets/user/td/mainboxwidget/client/grid/GridHeaderColumnMenu.java b/src/main/java/org/gcube/portlets/user/td/mainboxwidget/client/grid/GridHeaderColumnMenu.java
index 4823a4f..3c5a1ca 100644
--- a/src/main/java/org/gcube/portlets/user/td/mainboxwidget/client/grid/GridHeaderColumnMenu.java
+++ b/src/main/java/org/gcube/portlets/user/td/mainboxwidget/client/grid/GridHeaderColumnMenu.java
@@ -76,6 +76,11 @@ public class GridHeaderColumnMenu {
 		replaceValueOnConditionItem.setIcon(MainboxResources.INSTANCE.columnReplaceByExpression());	
 		menuItems.add(replaceValueOnConditionItem);
 		
+		MenuItem replaceValueByExternalItem = new MenuItem("Replace By External");
+		replaceValueByExternalItem.setId(GridHeaderOperationId.COLUMNREPLACEBYEXTERNAL.toString());
+		replaceValueByExternalItem.setIcon(MainboxResources.INSTANCE.columnReplaceByExternal());	
+		menuItems.add(replaceValueByExternalItem);
+		
 		
 		/*MenuItem newAnnotationColumnItem = new MenuItem("Annotation");
 		newAnnotationColumnItem.setId(GridHeaderOperationId.ANNOTATIONADD.toString());
diff --git a/src/main/java/org/gcube/portlets/user/td/mainboxwidget/client/resources/MainboxResources.java b/src/main/java/org/gcube/portlets/user/td/mainboxwidget/client/resources/MainboxResources.java
index 0a1e47f..d6ecb9b 100644
--- a/src/main/java/org/gcube/portlets/user/td/mainboxwidget/client/resources/MainboxResources.java
+++ b/src/main/java/org/gcube/portlets/user/td/mainboxwidget/client/resources/MainboxResources.java
@@ -109,4 +109,13 @@ public interface MainboxResources extends ClientBundle {
 	@Source("page-white.png")
 	ImageResource tabularResource();
 	
+	@Source("table-replace-by-external-col_32.png")
+	ImageResource columnReplaceByExternal32();
+
+	@Source("table-replace-by-external-col.png")
+	ImageResource columnReplaceByExternal();
+
+	
+	
+	
 }
diff --git a/src/main/java/org/gcube/portlets/user/td/mainboxwidget/client/resources/table-replace-by-external-col.png b/src/main/java/org/gcube/portlets/user/td/mainboxwidget/client/resources/table-replace-by-external-col.png
new file mode 100644
index 0000000..ed1ca28
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diff --git a/src/main/java/org/gcube/portlets/user/td/mainboxwidget/client/resources/table-replace-by-external-col_32.png b/src/main/java/org/gcube/portlets/user/td/mainboxwidget/client/resources/table-replace-by-external-col_32.png
new file mode 100644
index 0000000..f03d9f8
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diff --git a/src/main/resources/org/gcube/portlets/user/td/mainboxwidget/client/resources/table-replace-by-external-col.png b/src/main/resources/org/gcube/portlets/user/td/mainboxwidget/client/resources/table-replace-by-external-col.png
new file mode 100644
index 0000000..ed1ca28
Binary files /dev/null and b/src/main/resources/org/gcube/portlets/user/td/mainboxwidget/client/resources/table-replace-by-external-col.png differ
diff --git a/src/main/resources/org/gcube/portlets/user/td/mainboxwidget/client/resources/table-replace-by-external-col_32.png b/src/main/resources/org/gcube/portlets/user/td/mainboxwidget/client/resources/table-replace-by-external-col_32.png
new file mode 100644
index 0000000..f03d9f8
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