diff --git a/index.d.ts b/index.d.ts
index c589f5fb..1b4d079e 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1,3 +1,4 @@
+// Redux version 4.0.0
 // Type definitions for redux-devtools 3.4.1
 // TypeScript Version: 2.8.1