Apple has recalled adapter plugs sold with older iPhones amid concerns they might overheat.
"In rare cases," Apple warns, the 5W European USB power adapter "may overheat and pose a safety risk."
The adapter for European two-prong power sockets comes with the iPhone, and is also sold as a separate accessory. According to Apple, the only plugs with a problem are those that were sold with the iPhone 3GS, iPhone 4 and iPhone 4S between October 2009 and September 2012.
A redesigned version comes with more recent phones. If you have one of the older, potentially defective adapters, Apple will swap it for one of the redesigned versions.
If you bought an iPhone in that period and you're worried about your adapter, stop using it and take both your phone and the adapter to an Apple store or authorised service provider.
Once they've verified your phone's serial number they will swap the old adapter for a new one, and dispose of the offending article in an environmentally friendly way.
If your plug has already overheated and you had to replace it, you can contact Apple for a refund of the cost of the replacement.
Apple told CNET it has "voluntarily introduced a program for customers to exchange the Apple 5W European USB Power Adapter which came with iPhone 3GS, iPhone 4 and iPhone 4S models through September 2012, because in rare cases the adapter may overheat and pose a safety risk. For full program details, visit http://www.apple.com/support/usbadapter-european/."
To check your plug, look between the twin prongs: the affected adapter has the model number A1300 with the letters CE written in solid grey letters.
Should your plug have the model number A1300, with the letters CE outlined in grey, then you're OK. Have a look at this diagram to see the difference:
Most of Europe and the Nordic countries are included in the recall. Affected countries outside Europe include Egypt, South Africa and Vietnam. For more details and to check which countries are included, click on Apple's support page on the subject.