diff --git a/config_default.php b/config_default.php
index 10b1400..5b4b93c 100644
--- a/config_default.php
+++ b/config_default.php
@@ -91,7 +91,7 @@
      * The two first will be displayed in book entries
      * The other only appear in book detail
      */
-    $config['cops_prefered_format'] = array ("EPUB", "PDF", "MOBI", "CBR", "CBZ");
+    $config['cops_prefered_format'] = array ("EPUB", "PDF", "AZW3", "MOBI", "CBR", "CBZ");
     
     /*
      * use URL rewriting for downloading of ebook in HTML catalog