Apple is warning that its 5W European USB power adapter – the one that came with the iPhone 3GS, iPhone 4 and 4S between October 2009 and September 2012 – may overheat and pose a safety risk.
Consequently, the company is urging affected users to swap the existing units for new replacements which it is offering free of charge.
Apple notes that other 5W USB power adapters are not included in this replacement scheme.
The affected adapter is the A1300 model, which have the letters CE in solid grey. The new adapter, which isn’t affected, is an A1400 model and has the letters CE outlined in grey.
If you have one of these devices and live in one of the countries listed below, then you should get in touch with your local Apple store or other Apple Authorised Service Provider. You can also contact technical support to arrange an exchange.
The company says it will require your serial number in order to carry out the exchange, so don’t forget to take your phone with you too.
The official information regarding the fault is available on Apple’s website.