In bottom spin valves of the lead overlay type the longitudinal bias field that stabilizes the device tends to fall off well before the gap is reached. For example, according to one embodiment, a power distribution unit can include a component portion that comprises at least two modules selected from the group consisting of outlet modules, circuit protection modules, power input modules, communications IO modules, and display modules. The claws are fitted and hooked in an opening formed on a filter case, so that the fuel pump is protected from dropping out from the filter case.