Apple has issued a recall notice to some of its old USB iPhone chargers due to overheating problems that pose a safety threat.

Apple, the second largest smartphone manufacturer, has issued a recall notice for its old USB power adaptors due to concerns of overheating that pose a safety threat. The 5W European power adaptors, which Apple says may malfunction in rare cases, were sold between October 2009 and September 2012 across 37 countries. The Cupertino giant has advised its owners against using the power adaptor for charging purposes.

The affected power adaptor, as described by the tech giant, bears a distinct "CE" mark in solid gray color and "A1300" model number between the two sockets of the charger. The two-prong adaptors were sold along with the iPhone models and also as a separate accessory. According to Apple, the affected USB power adaptors were sold with the iPhone 3GS, iPhone 4 and iPhone 4S.

"Customer safety is always Apple's top priority, and we have voluntarily decided to exchange every affected power adapter for a new, redesigned adapter, free of charge," Apple said in its advisory note on its Support Pages. "We encourage customers to exchange any affected adapter for a new one as soon as possible using the exchange process below."

Apple's new chargers feature a different design and Apple is swapping the old models with the redesigned version for free.

If the overheating problem in the power adaptor occurred before Apple announced the recall, consumers can demand a refund paid towards the replacement in the past.

The defective chargers were sold mostly in Europe and the Nordic countries. The list of countries is given below.

Albania
Austria
Belgium
Bulgaria
Croatia
Czech Republic
Denmark
Egypt
Finland
France
Germany
Greece
Hungary
India
Indonesia
Israel
Italy
Latvia
Lithuania
Luxembourg
Macedonia
Moldova
Montenegro
Netherlands
Norway
Poland
Portugal
Romania
Russia
Slovakia
Slovenia
South Africa
Spain
Sweden
Switzerland
Turkey
Vietnam