diff --git a/third_party/2and3/requests/auth.pyi b/third_party/2and3/requests/auth.pyi
index 09a6df76b..afd7ce525 100644
--- a/third_party/2and3/requests/auth.pyi
+++ b/third_party/2and3/requests/auth.pyi
@@ -18,7 +18,7 @@ CONTENT_TYPE_MULTI_PART = ...  # type: Any
 def _basic_auth_str(username: Union[bytes, Text], password: Union[bytes, Text]) -> str: ...
 
 class AuthBase:
-    def __call__(self, r: models.Request) -> models.Request: ...
+    def __call__(self, r: models.PreparedRequest) -> models.PreparedRequest: ...
 
 class HTTPBasicAuth(AuthBase):
     username = ...  # type: Any