An auto-calibration circuit or label is adapted to be used with different instruments. The auto-calibration circuit comprises a first plurality of electrical connections and at least one electrical connection. The first plurality of electrical connections is utilized by the different instruments to auto-calibrate. The first plurality of electrical connections includes a first plurality of contact areas. At least one electrical connection is utilized solely by the second instrument to auto-calibrate and includes at least one contact area. This electrical connection is distinct from the first plurality of electrical connections. The first plurality of electrical connections is routed directly from each of the first plurality of contact areas to a respective first or second common connection. The at least one electrical connection is routed directly from the at least one contact area to the respective first common connection, the second common connection or a no-contact area.