Rolleicord Ia

R'cord Ia has automatic film transportation mechanism which R'cord I doesn't have.
See the first frame in the film counting window, and after that the film will stop automatically at the next frame by depressing the middle of the film wind knob, and at the same time winding the film with it.
In spite of the inexpensive version of R' cameras, useful devices like this began to put on the Rolleicord series, too, and this series would have made steady progress after this model.