diff --git a/README.md b/README.md
index dd50740..d4d8a05 100644
--- a/README.md
+++ b/README.md
@@ -51,7 +51,7 @@ DefaultPreference.set('my key', 'my value').then(function() {console.log('done')
 function get(key:String):Promise<String>;
 function set(key:String, value:String):Promise<Void>;
 function clear(key:String):Promise<Void>;
-function getMultiple(keys:Array<String>):Promise<Object>;
+function getMultiple(keys:Array<String>):Promise<Array<String>>;
 function setMultiple(data:Object):Promise<Void>;
 function clearMultiple(keys:Array<String>):Promise<Void>;
 function getAll():Promise<Object>;