We have Brown Porcelain Door Knobs door plates and mortise Vintage items.  The center bar is square feeding through the mortise (which works fine).  They measure about 5 1/2" from one side of the door knob to the opposing side.  The knobs are about 2 1/2" across the face of the knob x about 2 1/4" in D.  The metal building up to the porcelain on the knobs is metal and completly rusted.  There are 2 door plates, round on the bar in the center.  The mortise measures about 3 1/4" in l x about 2 7/8" in L on the face plate where the plunger is and about 7/8" in w on the same plate.  I would consider the set in fair condition with some rust, paint splatter and the knobs have some small blemishes. 

Door Knobs Brown Porcelain door plates and Mortise Vintage