The country you are choosing to travel to uses three types of plug, the US type three pin, the AUS/NZ three pin plug and the European 2 pin.
Either buy one of each if you are travelling extensively or please research the region your are travelling to in order that you can make the correct selection.
UK to Type F 2-socket Lite adapter
Use UK plugs in Europe, Egypt, Iceland, Russia & Vietnam
UK to Type B 2-socket Lite adapter
Use UK plugs in USA, Canada, Caribbean, Mexico & Japan
UK to Type I 2-socket Lite adapter
Use UK plugs in Australia, New Zealand, China, Argentina & Pacific Islands