High voltage transmission pylon with 5 lines (3 live wires and 2 'ground' wires, although feel free to use all 5). Simply place a series of foundations in-game, and paste this blueprint on top of them. The pylon will take the orientation of the foundation, so be sure to confirm the foundation's rotation in the 'update position' dialogue.

When planning your layout, please note that the max length of a wire is 100m (that includes elevation).