This is a template attribute. Template attributes can be used in filtering, or to retrieve data from the model to use in drawings and reports. For example, when you create a report, Tekla Structures replaces the attributes added in the report template with the corresponding object property values.

Shows the values entered in the Tension, T box on the End codes tab in the user-defined attributes dialog box of the part. axial1 shows the value in the Start box and axial2 in the End box.