diff --git a/index.d.ts b/index.d.ts
index f2ab26e..fa64e70 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1,3 +1,9 @@
 export default class DetailsDialogElement extends HTMLElement {
   toggle(open: boolean): void;
 }
+
+declare global {
+  interface Window {
+    DetailsDialogElement: typeof DetailsDialogElement
+  }
+}