An accessory computing device or display detachable from another computing device such as a mobile computing device. According to the method, one of the client and server roles is assigned to each of the two nodes based on a rule. The filter element has a collapsible filter body with a proximal inlet end and a distal outlet end. After filling the storage level to its full capacity, a microprocessor in combination with an incremental encoder, selects and matches a set of boards from the stored inventory, while continuously restoring its full capacity, and queuing the best blended order of contiguous boards. Each hole includes a flange area for accommodating deflection of the probes, inserted in the holes extending through the probe plates.