diff --git a/htdocs/core/lib/product.lib.php b/htdocs/core/lib/product.lib.php
index d811a3edfd1..391e180e839 100644
--- a/htdocs/core/lib/product.lib.php
+++ b/htdocs/core/lib/product.lib.php
@@ -153,7 +153,7 @@ function product_admin_prepare_head($object=null)
 	$head[$h][2] = 'general';
 	$h++;
 
-	if ($conf->global->MAIN_FEATURES_LEVEL > 1)
+	if ($conf->global->MAIN_FEATURES_LEVEL > 1)	// Link to page to make mass editing of products vat
 	{
 		$head[$h][0] = DOL_URL_ROOT.'/product/admin/product_tools.php';
 		$head[$h][1] = $langs->trans("Tools");
diff --git a/htdocs/product/admin/product_tools.php b/htdocs/product/admin/product_tools.php
index 7afe44418e9..dd8066cebed 100644
--- a/htdocs/product/admin/product_tools.php
+++ b/htdocs/product/admin/product_tools.php
@@ -21,6 +21,9 @@
  *  \brief      Setup page of product module
  */
 
+// TODO We must add a sentence to explain goal of page
+// TODO We must add a confirmation on button because this will make a mass change
+
 require '../../main.inc.php';
 require_once DOL_DOCUMENT_ROOT.'/core/lib/admin.lib.php';
 require_once DOL_DOCUMENT_ROOT.'/core/lib/product.lib.php';
@@ -165,7 +168,7 @@ print '</div>';
 
 // Boutons actions
 print '<div class="tabsAction">';
-print '<input type="submit" id="convert_vatrate" name="convert_vatrate" value="'.$langs->trans("Convert").'" />';
+print '<input type="submit" id="convert_vatrate" name="convert_vatrate" value="'.$langs->trans("Convert").'" class="button" />';
 print '</div>';
 
 print '</form>';