diff --git a/rx-angular/rx.angular.d.ts b/rx-angular/rx.angular.d.ts
index e2d0ec8c5..2b82e529a 100644
--- a/rx-angular/rx.angular.d.ts
+++ b/rx-angular/rx.angular.d.ts
@@ -10,7 +10,7 @@
 declare module Rx {
 
     interface IObservable<T> {
-        safeApply($scope: ng.IScope, callback: (data: any) => void): Rx.Observable<any>;
+        safeApply($scope: ng.IScope, callback: (data: T) => void): Rx.Observable<T>;
     }
 }