Out in the middle of nowhere, cool bow and arrow or Wishbone arm construction. Primary line was usually two phases on lower arm with top bracket on pole, this style arm shown was used to swap phases to prevent capacitive coupling. This line followed route 80 (previously the plank road) from Holtville CA to Yuma AZ
If anyone has history on this line, please let me know. I have found Many 4321 Victor insulators on this line in both grey and tan.
Edit: The line was finished by April 1917 by E F Sanguinetti of Yuma AZ. ''A new 55000 volt transmission line will connect the Holtville Power Station to Hanlon Heading on the California side of the Colorado River, with provision to supply Yuma residents. The line is to be of wood timber construction and a distance of 60 miles. There will also be a telephone line in conjunction.''- From Electrical Review, 1916
So I guess it officially is an antique. Interesting note, Sanguinetti was literally the founder of Yuma AZ.