Here is an original Stromberg Carlson telephone subset ringer box made of metal.
It has been beautifully restored. You will need this to add a ringer or network to your antique telephone. The brass bells are black powder coated or you can chose them in a fresh new nickel finish which costs a little extra . The wall cord is a brown cloth covered cord that has been added with a modular plug . All you have to do is plug it in.
Everything has been done for you. It works and rings well.