diff --git a/bowser/bowser.d.ts b/bowser/bowser.d.ts
index afd15fa5d..834532d37 100644
--- a/bowser/bowser.d.ts
+++ b/bowser/bowser.d.ts
@@ -42,7 +42,7 @@ declare module BowserModule {
         /** Grade X browser */
         x: boolean;
         name: string;
-        version: string;
+        version: string|number;
         osversion: string|number;
     }