Support frame for fitting in a carrier structure, wherein: a) the support frame borders a free surface into which at least one cover element can be inserted; b) the support frame is intended to be mounted in a cutout in the carrier structure; c) the cover element serves as a carrier of a functional unit or is constituted, unequipped, as a blind cover; d) the support frame is provided with systematically distributed bearings, in each of which a latch is guided so as to be pivotable from a released position into locked positions; e) each latch has an arm which, in the locked position, is intended to be placed on a rear surface, which surrounds the cutout, of the carrier structure; f) each bearing has arresting contours (541, 542) which, in interaction with a stopper present on the latch, form locked positions of the latch, from which positions the pivoting-back of the latch into its released position is blocked; g) the arresting contours (541, 542) comprise a first arresting contour in the form of an elevation, which is present on the bearing, for a first locked position of the latch; and h) the first arresting contour is configured at the very top of the bearing with a wedge shape which lowers in the direction of an inner surface on the bearing, which inner surface faces the free surface of the support frame, and terminates in a diametrical direction towards an outer surface on the bearing with a steep impact surface, characterized in that i) for a second locked position of the latch, the arresting contours (541, 542) comprise a second arresting contour which is arranged on the outer surface on the bearing and is thus outwardly offset with respect to the impact surface of the first arresting contour diametrically relative to the inner surface. a) the support frame borders a free surface into which at least one cover element can be inserted; b) the support frame is intended to be mounted in a cutout in the carrier structure; c) the cover element serves as a carrier of a functional unit or is constituted, unequipped, as a blind cover; d) the support frame is provided with systematically distributed bearings, in each of which a latch is guided so as to be pivotable from a released position into locked positions; e) each latch has an arm which, in the locked position, is intended to be placed on a rear surface, which surrounds the cutout, of the carrier structure; f) each bearing has arresting contours (541, 542) which, in interaction with a stopper present on the latch, form locked positions of the latch, from which positions the pivoting-back of the latch into its released position is blocked; g) the arresting contours (541, 542) comprise a first arresting contour in the form of an elevation, which is present on the bearing, for a first locked position of the latch; and h) the first arresting contour is configured at the very top of the bearing with a wedge shape which lowers in the direction of an inner surface on the bearing, which inner surface faces the free surface of the support frame, and terminates in a diametrical direction towards an outer surface on the bearing with a steep impact surface, characterized in that i) for a second locked position of the latch, the arresting contours (541, 542) comprise a second arresting contour which is arranged on the outer surface on the bearing and is thus outwardly offset with respect to the impact surface of the first arresting contour diametrically relative to the inner surface.