diff --git a/admin/box.php b/admin/box.php
index 09c83d4f..5f52c2bb 100644
--- a/admin/box.php
+++ b/admin/box.php
@@ -10,6 +10,8 @@ class P2P_Box {
 
 	private $columns;
 
+	private $labels;
+
 	private static $enqueued_scripts = false;
 
 	private static $admin_box_qv = array(