Abstract: The connection of an accessory to a suction disc module comprises a lever mounted to the suction disc module; a latch bar on each side of that lever, and a raised shoulder on a top surface of the lever. The accessory has a pair of inclined latch blocks for engagement with the latch bars and a square-edge boss for engagement with the raised shoulder. The lever is urged away from the suction disc module by a spring. The lever has an overrun in a displacement thereof while a displacement of the spring remains constant. The lever is selectively movable along this overrun for engaging the latch bars with the inclined latch blocks and for engaging the raised shoulder with the square-edge boss. This latter engagement of the raised shoulder with the square-edge boss prevents an excess movement of the connecting direction, and urges the accessory in the release direction.