diff --git a/jwst/extract_1d/apply_apcorr.py b/jwst/extract_1d/apply_apcorr.py
index 5620d8f49a..3618719f89 100644
--- a/jwst/extract_1d/apply_apcorr.py
+++ b/jwst/extract_1d/apply_apcorr.py
@@ -71,9 +71,8 @@ def __init__(self, input_model, apcorr_table, sizeunit,
         self.tabulated_correction = None
 
     @property
-    @abc.abstractmethod
     def size_key(self):
-        ...
+        return None
 
     def _convert_size_units(self):
         """If the SIZE or Radius column is in units of arcseconds, convert to pixels."""