Because of the way these knobs were constructed gives us a clue that they are quite old. The top of the knob has been snapped or crimped onto the base. A knob very much like this was manufactured by Russell and Erwin in 1909 and backed by a plain, undecorated back plate.
The knobs have a flat face with a raised edge. They are belted, as a result of the top piece being clamped onto the base. Each knobs measures 2 1/4 inches across and 1 1/8 inches deep.
The knobs are in very good condition. There are no dents. A spindle and two set screws are included.