The gaps between the doors or door leaf and the jamb cover strip, typically of the rack, attaching it with the overlap to the free edge of the door. If the rail is narrow, it is poorly kept. If wide, it looks ugly. Head fasteners too difficult to hide. Better batten to make moldings, t-section or double angles (they make those now made of composite materials), attaching their edges to a vertical edge of the door.
A. RODIN