diff --git a/types/express-serve-static-core/index.d.ts b/types/express-serve-static-core/index.d.ts
index a54481027d..8e1f075f03 100644
--- a/types/express-serve-static-core/index.d.ts
+++ b/types/express-serve-static-core/index.d.ts
@@ -1,6 +1,6 @@
 // Type definitions for Express 4.x
 // Project: http://expressjs.com
-// Definitions by: Boris Yankov <https://github.com/borisyankov/>
+// Definitions by: Boris Yankov <https://github.com/borisyankov/>, Michał Lytek <https://github.com/19majkel94>
 // Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
 // This extracts the core definitions from express to prevent a circular dependency between express and serve-static
 /// <reference types="node" />
@@ -168,6 +168,10 @@ interface CookieOptions {
     sameSite?: boolean | string;
 }
 
+interface ByteRange { start: number; end: number; }
+
+interface RequestRanges extends Array<ByteRange> { type: string; }
+
 interface Errback { (err: Error): void; }
 
 interface Request extends http.IncomingMessage, Express.Request {
@@ -298,7 +302,7 @@ interface Request extends http.IncomingMessage, Express.Request {
         *
         * @param size
         */
-    range(size: number): any[];
+    range(size: number): RequestRanges|null|-1|-2;
 
     /**
         * Return an array of Accepted media types