The overhead line network is divided into sections that are approximately 1.2 kilometres long. This is done to be able to control that the overhead line is sufficiently tensioned. Usually, at each end of an overhead line section, there is a tension pole. To compensate for the length changes of the overhead line that occur with temperature fluctuations, the overhead line is stretched using weights.

This pole is equipped with a strut of U-beam to absorb the tension forces that occur when the overhead line and return conductor are tensioned.

Other overhead line poles usually do not need to be supported with braces and struts. But where the entire tensioning force of the line is to be absorbed, the pole must be strutted. Struts are used because they are both more resistant to rust attack and withstand mechanical damage better than steel wire braces.