The FM21X103K251ECG is a multilayer ceramic capacitor (MLCC) manufactured by Prosperity. It has a capacitance of 10nF (nanofarads), a working voltage of 250V, and is packaged in an 0805 surface-mount technology (SMT) format. In addition, it is RoHS compliant, meaning that its materials meet environmental regulations set by the European Union. This capacitor is suited for a variety of applications such as filters, signal processing, and tuning circuits.