In a power storage pack, a power storage unit supplies electric power to an electric mobile body. A wireless communication unit performs short-range wireless communication. A notification unit presents, to a user of a mobile terminal device, a tentative notification of a verification code that is to be used in the process of exchanging an encryption key that is to be used for the short-range wireless communication with the mobile terminal device. The notification unit may include a remaining capacity display for the power storage unit.