diff --git a/molpipeline/explainability/explainer.py b/molpipeline/explainability/explainer.py
index 36bed9dd..2fffb79f 100644
--- a/molpipeline/explainability/explainer.py
+++ b/molpipeline/explainability/explainer.py
@@ -174,6 +174,8 @@ def explain(self, X: Any, **kwargs: Any) -> Return_type_:
 class _SHAPExplainerAdapter(AbstractSHAPExplainer, abc.ABC):
     """Adapter for SHAP explainer wrappers for handling molecules and pipelines."""
 
+    Return_type_ = AbstractSHAPExplainer.Return_type_
+
     def __init__(
         self,
         pipeline: Pipeline,