diff --git a/apiclient/model.py b/apiclient/model.py
index fda4ef2..9881a15 100644
--- a/apiclient/model.py
+++ b/apiclient/model.py
@@ -141,7 +141,7 @@
       headers['user-agent'] += ' '
     else:
       headers['user-agent'] = ''
-    headers['user-agent'] += 'google-api-python-client/' + __version__
+    headers['user-agent'] += 'google-api-python-client/%s (gzip)' % __version__
 
     if body_value is not None:
       headers['content-type'] = self.content_type
diff --git a/tests/test_json_model.py b/tests/test_json_model.py
index d461e4c..96570f6 100644
--- a/tests/test_json_model.py
+++ b/tests/test_json_model.py
@@ -140,7 +140,8 @@
         headers, path_params, query_params, body)
 
     self.assertEqual(headers['user-agent'],
-        'my-test-app/1.23.4 google-api-python-client/' + __version__)
+        'my-test-app/1.23.4 google-api-python-client/' + __version__ +
+        ' (gzip)')
 
   def test_bad_response(self):
     model = JsonModel(data_wrapper=False)