Flexible steel arm for hands-free calling, 1948

This was how hand-free calling worked, according to the September, 1948 ish of Popular Mechanics:

Holding the telephone ready for use, a "third hand" of flexible steel leaves both the operator's hands free to take notes during phone conversations. The spring arm holds the receiver to the ear and can be adjusted to the height and position of the user. The third hand was developed in Australia.