   # destory old models from the collection which have not marked as "new"
   destroyDiff: (response) ->
     diff = _.difference(_.without(@items.pluck('sid'), 'new'), _.pluck(response, 'id'))
-    this.get(sid)?.destroy(local: true) for sid in diff
+    @get(sid)?.destroy(local: true) for sid in diff
 
   # Use to create a fake model for the set
   fakeModel: (sid) ->
-    model = new Backbone.Model()
-    model.id = sid
+    model = new Backbone.Model(id: sid)
     model.urlRoot = @items.url
-
-    return model
+    model


  ajax: (method, model, options) ->
    if Offline.onLine()
      this.prepareOptions(options)
      Backbone.ajaxSync(method, model, options)
    else
      @storage.setItem('offline', 'true')

  add: (itemId) ->
    unless _.include(@values, itemId.toString())
      @values.push itemId.toString()
    @save()

  # Remove element from a list of values
  # records.remove '3'
