diff --git a/boards/models/attachment/viewers.py b/boards/models/attachment/viewers.py
--- a/boards/models/attachment/viewers.py
+++ b/boards/models/attachment/viewers.py
@@ -6,6 +6,7 @@ FILE_STUB_IMAGE = 'images/file.png'
 FILE_TYPES_VIDEO = (
     'webm',
     'mp4',
+    'mpeg',
 )
 FILE_TYPE_SVG = 'svg'
 FILE_TYPES_AUDIO = (