The Attribute Holder modifier is an empty modifier that provides a readily accessible user interface on the Modify panel to which you can add custom attributes. It has no user interface of its own; the interface consists solely of those attributes you assign to it. In essence, Attribute Holder is a stripped-down version of Parameter Collector that can collect only custom attributes and appears on the Modify panel instead of a floating dialog.
Sometimes completely unknown, the modifiers are very useful during the normal workflow of 3dsMax. These are old videos created with 3dsMax2010 but the modifiers are equal to the latest versions
