diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index ade8a59..7011cdd 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -3,7 +3,7 @@ repos:
     rev: stable
     hooks:
       - id: black
-        language_version: python3.7
+        language_version: python3.8
   - repo: https://gitlab.com/pycqa/flake8
     rev: ""
     hooks:
diff --git a/python_graphql_client/graphql_client.py b/python_graphql_client/graphql_client.py
index 2787971..a6164a5 100644
--- a/python_graphql_client/graphql_client.py
+++ b/python_graphql_client/graphql_client.py
@@ -47,7 +47,9 @@ def execute(
         )
 
         result = requests.post(
-            self.endpoint, json=request_body, headers=self.__request_headers(headers),
+            self.endpoint,
+            json=request_body,
+            headers=self.__request_headers(headers),
         )
 
         result.raise_for_status()
@@ -92,7 +94,9 @@ async def subscribe(
         )
 
         async with websockets.connect(
-            self.endpoint, subprotocols=["graphql-ws"]
+            self.endpoint,
+            subprotocols=["graphql-ws"],
+            extra_headers=self.__request_headers(headers),
         ) as websocket:
             await websocket.send(connection_init_message)
             await websocket.send(request_message)
@@ -100,5 +104,7 @@ async def subscribe(
                 response_body = json.loads(response_message)
                 if response_body["type"] == "connection_ack":
                     logging.info("the server accepted the connection")
+                elif response_body["type"] == "ka":
+                    logging.info("the server sent a keep alive message")
                 else:
                     handle(response_body["payload"])
diff --git a/tests/test_graphql_client.py b/tests/test_graphql_client.py
index a35980e..a3d408f 100644
--- a/tests/test_graphql_client.py
+++ b/tests/test_graphql_client.py
@@ -248,3 +248,62 @@ async def test_subscribe(self, mock_connect):
                 call({"data": {"messageAdded": "two"}}),
             ]
         )
+
+    @patch("logging.info")
+    @patch("websockets.connect")
+    async def test_does_not_crash_with_keep_alive(self, mock_connect, mock_info):
+        """Subsribe a GraphQL subscription."""
+        mock_websocket = mock_connect.return_value.__aenter__.return_value
+        mock_websocket.send = AsyncMock()
+        mock_websocket.__aiter__.return_value = [
+            '{"type": "ka"}',
+        ]
+
+        client = GraphqlClient(endpoint="ws://www.test-api.com/graphql")
+        query = """
+            subscription onMessageAdded {
+                messageAdded
+            }
+        """
+
+        await client.subscribe(query=query, handle=MagicMock())
+
+        mock_info.assert_has_calls([call("the server sent a keep alive message")])
+
+    @patch("websockets.connect")
+    async def test_headers_passed_to_websocket_connect(self, mock_connect):
+        """Subsribe a GraphQL subscription."""
+        mock_websocket = mock_connect.return_value.__aenter__.return_value
+        mock_websocket.send = AsyncMock()
+        mock_websocket.__aiter__.return_value = [
+            '{"type": "data", "id": "1", "payload": {"data": {"messageAdded": "one"}}}',
+        ]
+
+        expected_endpoint = "ws://www.test-api.com/graphql"
+        client = GraphqlClient(endpoint=expected_endpoint)
+
+        query = """
+            subscription onMessageAdded {
+                messageAdded
+            }
+        """
+
+        mock_handle = MagicMock()
+
+        expected_headers = {"some": "header"}
+
+        await client.subscribe(
+            query=query, handle=mock_handle, headers=expected_headers
+        )
+
+        mock_connect.assert_called_with(
+            expected_endpoint,
+            subprotocols=["graphql-ws"],
+            extra_headers=expected_headers,
+        )
+
+        mock_handle.assert_has_calls(
+            [
+                call({"data": {"messageAdded": "one"}}),
+            ]
+        )