diff --git a/src/component/overlay.vue b/src/component/overlay.vue
index 2149e7c9..aea19d92 100644
--- a/src/component/overlay.vue
+++ b/src/component/overlay.vue
@@ -455,8 +455,8 @@
     // implicit hosting
     //
 
-    private reqMouseDown: any | null = null
-    private reqMouseUp: any | null = null
+    private reqMouseDown: MouseEvent | null = null
+    private reqMouseUp: MouseEvent | null = null
 
     @Watch('isControling')
     onControlChange(isControling: boolean) {