Apple is offering free replacement batteries for some iPhone 5 models.

The company says a small percentage of its iPhone 5 smartphones purchased between Sept. 2012 and Jan. 2013, “may suddenly experience a shorter battery life or need to be charged more frequently.”

IPhone owners  can use a serial number checker on the Apple website to determine if they’re eligible for the program, which will see phone batteries replaced free of charge.

The battery replacement is currently available in the U.S. and China and it will be rolled out in other countries as of Aug. 29.

Earlier this year Apple offered to fix some iPhone 5 models with faulty on-off buttons.