A modular closure device for different closure elements, such as finger levers, plate cylinders, profile cylinders, profile half cylinders, for locking a pivot lever in a recess, is described, wherein the closure elements can be inserted and fastened in a receptacle arranged in the recess or the pivot lever, either from the front or from the rear, characterised in that the closure device, which has an interchangeable insert adapted to the closure device and having a different design for the various receptacles, interacts with a guide in such a way that this can be inserted into the recess or into the pivot lever, and the recess or the pivot lever having the inserted interchangeable insert can be plugged in a door leaf through an opening in the door leaf or the like and can be fastened with a cap.