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.

These attributes show the values entered for Tension, Nt on the End conditions tab in the user-defined attributes dialog box of the part. axial1 shows the value in the Start box and axial2 shows the value in the End box.