diff --git a/stdlib/2and3/mmap.pyi b/stdlib/2and3/mmap.pyi
index 2f4978f2b..de5b40208 100644
--- a/stdlib/2and3/mmap.pyi
+++ b/stdlib/2and3/mmap.pyi
@@ -73,8 +73,8 @@ if sys.version_info >= (3,):
         @overload
         def __setitem__(self, index: slice, object: bytes) -> None: ...
 else:
-    class mmap(_mmap, Sequence[str]):
-        def rfind(self, string: str, start: int = ..., stop: int = ...) -> int: ...
-        def __getitem__(self, index: Union[int, slice]) -> str: ...
+    class mmap(_mmap, Sequence[bytes]):
+        def rfind(self, string: bytes, start: int = ..., stop: int = ...) -> int: ...
+        def __getitem__(self, index: Union[int, slice]) -> bytes: ...
         def __delitem__(self, index: Union[int, slice]) -> None: ...
-        def __setitem__(self, index: Union[int, slice], object: str) -> None: ...
+        def __setitem__(self, index: Union[int, slice], object: bytes) -> None: ...