Type of property created on the User tab of the Properties dialog box for the element or object. User-defined properties are usually in the form of a text notation, such as cost and manufacturer. You can change user-defined properties, but these changes have no affect on the appearance of the element or object. For example, user-defined properties stored with a valve symbol can include the manufacturer, cost, or material. User-defined properties are displayed in the Attribute Viewer when you select the valve symbol.