diff --git a/src/type_def.h b/src/type_def.h
index ce1435c3..e35257b1 100644
--- a/src/type_def.h
+++ b/src/type_def.h
@@ -74,7 +74,7 @@ namespace etl
         }
 
         //*********************************************************************
-        explicit operator TValue() const
+        operator TValue() const
         {
             return value;
         }