An apparatus for magnetic recording having a barrier layer. The apparatus includes a right-angled hook, a curved hook, a connecting body and an adjusting member. In a specific embodiment of the invention, power planes are coupled through the substrate to front side metal lines, well taps and external connection points. Since the measurement is performed only at one end of the conductive line to test the open or short circuit of the conductive line, it is possible to self-diagnose the open or short circuit when a single-side probe device is mounted in an inputoutput port of an electrical device. The second casing is provided with a second tank mounting portion and a liquid transferring portion. The interlock arrangement further includes a retainer for preventing inadvertent disengagement of the inner engagement members from the interlock base member.