Brookfield invented/developed the CD 152 and was called "the new Brookfield insulator" and "A new type of Brookfield insulator" in 1912 and 1913 by Telephony and Electrical Review magazines respectively.

A.T.&.T and W.U.T. adopted it for usage on their long distance telephone lines (as well as railroads using it).

Mechanical strength and electrical efficiency cited.