You are looking at a set of Antique Brass Doorknobs dating roughly from the mid 1920s.
These particular doorknobs came from the same house as the other set of knobs I have listed that look similar - This particular knob is intended for a side door, hence why the one side has a oval deadbolt lock.
Not included is the mechanism that this would go with - it was unable to be salvaged, unfortunately.
The knobs themselves have a diameter of 2", and they are 1 3/4" tall.
The backplates measure approximately 5 1/2" tall, and are 1 3/4" at their widest.