Such pole-line construction was fairly recent and commonplace in its day on Cape Cod communities including the New England Telephone and Telegraph Company 10-pin subscriber openwire. The electric utility that served this community was the Cape and Vineyard Electric Company. Some older poles like this with similar primaries and secondary racks still remain on the Cape particularly where 4kv primary conversions haven't taken place. The phone openwire went in the 60s in favor of paired cable.