code: function() {
              for (var i = 0; i < this.helpers.length; i++) {
                  (function($draggeeHelper) {
                      $draggeeHelper.velocity('fadeOut', {
                          duration: Garnish.FX_DURATION,
                          complete: function() {
                              $draggeeHelper.remove();
                          }
                      });
                  })(this.helpers[i]);
              }
          }
docs: Fade Out Helpers