diff --git a/web3/datastructures.py b/web3/datastructures.py
index eba2e9ac02..dfae1b7dca 100644
--- a/web3/datastructures.py
+++ b/web3/datastructures.py
@@ -261,7 +261,7 @@ def __iter__(self) -> Iterator[TKey]:
 
     def __add__(self, other: Any) -> "NamedElementOnion[TKey, TValue]":
         if not isinstance(other, NamedElementOnion):
-            raise NotImplementedError(
+            raise NotImplemented(
                 "You can only combine with another NamedElementOnion"
             )
         combined = self._queue.copy()