Representatives are templates for 1D objects with the identical properties with regard to the material, cross-section, member type, and length. These representatives can be understood as "member templates". They facilitate the evaluation and documentation of results. Since only a member or a member set with the governing internal forces of all similar types is analyzed, the representatives provide a good overview in both the program and the printout.
General information about using representatives can be found in the RFEM manual in Chapter Member representatives and Member Set Representatives.
For the design, select the corresponding representative in Objects to Design. Here, you can also activate the individual members or member sets for the design if you want to output them for several object types.