More to explore:
Cover of a Plan-It Insulated-Metal Framed Structures brochure, circa 1950s. Plan-It Homes, located in Sherman Oaks, designed pre-fabricated metal framed buildings. The brochure explains Plan-It structures are: "designed and engineered for the ultimate in fast, simple construction under all conditions, adaptability, and low maintenance . . ." Brochure also claims that unskilled workers could easily erect a Plan-It structure in a matter of hours. San Fernando Valley History Digital Library.
this is what power lines used to look like..they had the glass insulators