The electrical
current in Great Britain is 220 / 240 volts (in line with the
rest of Europe), 50 cycles alternating current AC (for the technical
amongst you). Wall sockets take three-pin plugs and shaver sockets
take two round, oversize prongs.
To use U.S.
electric-powered equipment you'll need a converter and an adapter
plug (or just an adapter if your appliances are dual-voltage).
Don't use
110-volt outlets marked "For Shavers Only" for high-wattage
appliances such as hair dryers.
London
Hotels (these links are to another website)