diff --git a/sandbox/embed_selfhost_multiple.html b/sandbox/embed_selfhost_multiple.html
index 2e7f2a9..3d15889 100644
--- a/sandbox/embed_selfhost_multiple.html
+++ b/sandbox/embed_selfhost_multiple.html
@@ -69,7 +69,9 @@
 	<!-- importer end -->
 
     <script type='text/javascript'>
-        OV.Init3DViewerElements ();
+        OV.Init3DViewerElements (function (viewers) {
+			viewers[0].viewer.renderer.setClearColor ('#222222', 1.0);
+		});
     </script>
 
     <style>
diff --git a/source/viewer/domviewer.js b/source/viewer/domviewer.js
index 326ad40..fc34670 100644
--- a/source/viewer/domviewer.js
+++ b/source/viewer/domviewer.js
@@ -1,4 +1,4 @@
-OV.Init3DViewerElements = function ()
+OV.Init3DViewerElements = function (onReady)
 {
     function LoadElement (element)
     {
@@ -89,6 +89,9 @@ OV.Init3DViewerElements = function ()
             let viewerElement = LoadElement (element);
             viewerElements.push (viewerElement);
         }
+        if (onReady !== undefined && onReady !== null) {
+            onReady (viewerElements);
+        }
     }); 
 
     window.addEventListener ('resize', function () {
@@ -99,6 +102,4 @@ OV.Init3DViewerElements = function ()
             viewerElement.viewer.Resize (width, height);    
         }
     });
-
-    return viewerElements;
 };