This is a regulated universal plug-in power supply with a selector switch for 7 different output voltages between 3v and 12v.  It is fitted with an On/Off LED indicator and comes with 7 adaptor plugs for connecting to different appliances.  This unit aslo has switcheable polarity by reversing any of the seven plugs.  This can be used to power a number of our devices including the digital recorder so that the full recording capacity can be utilised without changing batteries.