diff --git a/eta/core/web.py b/eta/core/web.py
index 88989cc1c..34c41b6c8 100644
--- a/eta/core/web.py
+++ b/eta/core/web.py
@@ -87,7 +87,8 @@ def download_google_drive_file(fid, path=None, chunk_size=None):
 class WebSession(object):
     """Class for downloading files from the web."""
 
-    DEFAULT_CHUNK_SIZE = None
+    # Chunk size, in bytes
+    DEFAULT_CHUNK_SIZE = 64 * 1024
 
     def __init__(self, chunk_size=None):
         """Creates a WebSession instance.