I believe the voltage upon the upper circuits was 11kv. In the foreground is a "riser pole" which provided for underground service. The cabling was connected atop the pole and installed through a metal pipe that ran down along the pole. Special high voltage cable is required for this. In the background is a KPF (brand) "side-winder" switch which enabled all three conductors of the circuit to be physically connected or disconnected. These rather unique switches were made in the SF area and gained widespread popularity in the US through the years since they could be vertically (as shown) mounted or horizontally. I believe they were rated from 11kv to 115kv. Most employed suspension insulators as deadends. However I have seen line posts (light gray as well as brown) used for this purpose, especially within the New England Electric Service region. Photograph taken around 1972 in Carson, CA along East 213th Street near the intersection of Viera Street.

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