diff --git a/sockjs/sockjs.d.ts b/sockjs/sockjs.d.ts
index 7a4316ad6..db58683b2 100644
--- a/sockjs/sockjs.d.ts
+++ b/sockjs/sockjs.d.ts
@@ -36,10 +36,17 @@ interface SockJS extends EventTarget {
 
 declare var SockJS: {
     prototype: SockJS;
-    new (url: string, options?: {
-         debug: boolean;
-         devel: boolean;
-         protocols_whitelist: string[];
-     }): SockJS;
-
-}
\ No newline at end of file
+    new (url: string, _reserved: any, options?: {
+        debug?: boolean;
+        devel?: boolean;
+        protocols_whitelist?: string[];
+        server?: string;
+        rtt?: number;
+        rto?: number;
+        info?: {
+            websocket?: boolean;
+            cookie_needed?: boolean;
+            null_origin?: boolean;
+        };
+    }): SockJS;
+};
\ No newline at end of file