A USB device including a housing and a protective cap that are slidably and/or pivotably connected together such that the protective cap is able to slide and/or pivot between an open position, in which a plug connector extending from the front of the housing is exposed for operable coupling to a host system, and a closed position, in which the protective cap is disposed over the front end portion of the housing to protect the plug connector. A pivoting/sliding mechanism is provided on the housing and cap that secures the protective cap to the housing at all times, including during transitional movements of the protective cap between the opened and closed positions.