diff --git a/dataclass_csv/dataclass_writer.py b/dataclass_csv/dataclass_writer.py
index fdcbb52..4e8f27c 100644
--- a/dataclass_csv/dataclass_writer.py
+++ b/dataclass_csv/dataclass_writer.py
@@ -11,7 +11,7 @@ def __init__(
         data: List[Any],
         cls: Type[object],
         dialect: str = "excel",
-        **fmtparams: Dict[str, Any],
+        **fmtparams: Any,
     ):
         if not f:
             raise ValueError("The f argument is required")
diff --git a/dataclass_csv/dataclass_writer.pyi b/dataclass_csv/dataclass_writer.pyi
index 9c0d76f..cd04635 100644
--- a/dataclass_csv/dataclass_writer.pyi
+++ b/dataclass_csv/dataclass_writer.pyi
@@ -8,7 +8,7 @@ class DataclassWriter:
         data: List[Any],
         cls: Type[object],
         dialect: str = ...,
-        **fmtparams: Dict[str, Any],
+        **fmtparams: Any,
     ) -> None: ...
     def write(self, skip_header: bool = ...) -> Any: ...
     def map(self, propname: str) -> HeaderMapper: ...