The re-insulation of an existing overhead line to a higher voltage requires an extensive planning approval procedure. This is because the re-insulation is not feasible for many mast geometries while maintaining the spacing between the conductor cable and the mast crossarm below. In addition, there are mechanical requirements for tensile loads, sag and deflection in wind, as well as ice load. With the use of an insulated suspension chain, re-insulation is possible while maintaining the same suspension point (NISV) and ground clearance, as well as unchanged mast statics. Poles with small horizontal and vertical distances cannot be insulated with standard chains.