Chain links and methods for forming chain links are provided. The fastener includes a first engaging surface having a maximum diameter configured to engage an interior surface of an opening in the first article and a mating surface configured to mate with the second article. The method further comprises placing one of the data storage devices in a standby state, operating the rest of the data storage devices in an active state, and controlling logical operations of the controller and the read and write operations of the active data storage devices to substitute for read and write operations on the standby device. Voltage measurements are taken directly from the PN junction. The concentration operator determines a concentration of evaporated fuel in the fuel tank based on the differential pressure detected when the opposite ends of the measurement passage communicate with the fuel tank and the fuel flows in the measurement passage. The multilayer electroplated stack may include one or more instances of alternating layers of gold and tin, where relative thicknesses of the alternating layers, when melted, result in a chemical composition having an initial melting temperature to form a bump and a subsequent melting temperature to reflow the bump that is higher than the initial melting temperature.