diff --git a/youtube_dl/extractor/iol.py b/youtube_dl/extractor/iol.py
index 3b268a859..1605ca7c3 100644
--- a/youtube_dl/extractor/iol.py
+++ b/youtube_dl/extractor/iol.py
@@ -63,7 +63,6 @@ class IOLIE(InfoExtractor):
                 'format_id': 'http_500',
                 'tbr': 500,
                 'protocol': 'http',
-                'protocol': 'http',
                 'preference': -1,
                 'no_resume': False
             })