diff --git a/stdlib/multiprocessing/heap.pyi b/stdlib/multiprocessing/heap.pyi
index 114bdf0d4..b5e2ced5e 100644
--- a/stdlib/multiprocessing/heap.pyi
+++ b/stdlib/multiprocessing/heap.pyi
@@ -27,7 +27,7 @@ if sys.platform != "win32":
     def rebuild_arena(size: int, dupfd: _SupportsDetach) -> Arena: ...
 
 class Heap:
-    def __init__(self, size: int = 4096) -> None: ...
+    def __init__(self, size: int = ...) -> None: ...
     def free(self, block: _Block) -> None: ...
     def malloc(self, size: int) -> _Block: ...