diff --git a/openflexure_microscope/common/flask_labthings/views/extensions.py b/openflexure_microscope/common/flask_labthings/views/extensions.py
index a4fcca41..65bb3e56 100644
--- a/openflexure_microscope/common/flask_labthings/views/extensions.py
+++ b/openflexure_microscope/common/flask_labthings/views/extensions.py
@@ -39,7 +39,7 @@ class ExtensionSchema(Schema):
             # Make links dictionary if it doesn't yet exist
             d[view_id] = {
                 "href": url_for(
-                    ExtensionListResource.endpoint, **view_kwargs, _external=True
+                    ExtensionList.endpoint, **view_kwargs, _external=True
                 )
                 + view_rule,
                 **description_from_view(view_cls),