diff --git a/src/calibre/gui2/actions/unpack_book.py b/src/calibre/gui2/actions/unpack_book.py
index d204554211..e61e2c07b8 100644
--- a/src/calibre/gui2/actions/unpack_book.py
+++ b/src/calibre/gui2/actions/unpack_book.py
@@ -287,7 +287,7 @@ class UnpackBookAction(InterfaceAction):
 
     name = 'Unpack Book'
     action_spec = (_('Unpack Book'), 'unpack-book.png',
-            _('Unpack books in the EPUB, AZW3, HTMLZ formats into their individual components'), None)
+            _('Unpack books in the EPUB, AZW3, HTMLZ formats into their individual components'), 'U')
     dont_add_to = frozenset(['context-menu-device'])
     action_type = 'current'