diff --git a/src/all.js b/src/all.js
index 8cd23bd5b1..cd16a8ce30 100644
--- a/src/all.js
+++ b/src/all.js
@@ -2,6 +2,7 @@ goog.provide('ol');
 
 goog.require('ol.Bounds');
 goog.require('ol.Camera');
+goog.require('ol.Extent');
 goog.require('ol.MVCArray');
 goog.require('ol.MVCObject');
 goog.require('ol.TileBounds');
diff --git a/src/ol/extent.js b/src/ol/extent.js
new file mode 100644
index 0000000000..58e2f764f3
--- /dev/null
+++ b/src/ol/extent.js
@@ -0,0 +1,28 @@
+goog.provide('ol.Extent');
+
+goog.require('goog.math.Box');
+
+
+
+/**
+ * @constructor
+ * @extends {goog.math.Box}
+ * @param {number} top Top.
+ * @param {number} right Right.
+ * @param {number} bottom Bottom.
+ * @param {number} left Left.
+ */
+ol.Extent = function(top, right, bottom, left) {
+
+  goog.base(this, top, right, bottom, left);
+
+};
+goog.inherits(ol.Extent, goog.math.Box);
+
+
+/**
+ * @return {ol.Extent} Extent.
+ */
+ol.Extent.prototype.clone = function() {
+  return new ol.Extent(this.top, this.right, this.bottom, this.left);
+};