<p>The voltage thing does need to be dealt with - I don’t know what country your son is planning on going to, but as an example the UK has 230V. The US has 120V. If you try and plug a US item straight into UK mains, it will blow up. </p>
<p>For small, cheap items it may be easier (both in terms of voltage and how much baggage he needs to take) to simply buy a cheap version when he gets to the UK, and donate it to a charity shop when he leaves - items like hairdryers are a good example. </p>
<p>For more important items like laptops, you’ll want a step down voltage converter, along these lines [US</a> to UK Step-Down Transformers](<a href=“http://www.accessorystore.co.uk/acatalog/us_uk_transformers.html]US”>http://www.accessorystore.co.uk/acatalog/us_uk_transformers.html) Make sure he gets one for the right country - different countries (and I believe sometimes, different regions within countries) have different styles of plugs. </p>
<p>I appreciate the difficulties - I bought a digital camera when I was working abroad, and so I now, forevermore, must use an adapter whenever I need to charge it back in the UK.</p>