All you need to test the site supply at source both in the UK and Europe. Especially useful for testing for polarity reversal. Use as follows :

UK 3-pin Socket : Mains Tester only.

European standard 3-pin Socket : Trailing Socket with Mains Tester.

Continental 2-pin Socket (Schuko): Continental Adaptor and Trailing Socket with Mains Tester.

The components can also be used separately.