This is one of those base units that you sit an iPod in, and it also provides clock/radio functions, right?
Power will just follow the same guidelines as most other similar units. My guess would be that it is most likely 120V only, in which case you'd need to run through a transformer. If there is a voltage selector on the back, or the label says something like 90 to 250 volts indicating a switched-mode supply, then it will work with just a change of plug or a plug adapter. I very much doubt that the clock on a modern unit will be synchronized to the supply frequency, but if for some reason it is then the clock will run slow.
If the radio section has digital tuning with fixed steps, then be aware that it may not be able to receive all British stations properly. See reply #3 in the
Technical issues thread for more about this.