Ways of allocating an identifier to a mobile device are disclosed. The third ceramic layers and the first and second outer layer portions contain a perovskite-type compound represented by ABO3 where A contains one or more of Ba, Sr, and Ca, B contains one or more of Ti, Zr, and Hf, and O represents oxygen) as a main component. A print media supply arrangement is positioned in the housing and incorporates a roll of print media.