A window or door fitting for actuation of a mechanism integrated in a window or a door has a stop body that can be attached to the window or the door, a handle, that is rotatably mounted on the stop body in an axially fixed manner, a polygonal element for the mechanical coupling of the fitting to the mechanism integrated in the window of the door, and a coupling configuration formed between the handle and the polygonal element, with which a torque transference from the handle to the polygonal element can be effected, but can be blocked in the direction from the polygonal element to the handle. The coupling configuration has two driving elements for this, wherein a first diving element is connected to the handle in a rotationally locked manner, while a second driving element accommodates the polygon in a rotationally fixed manner.