Duracell microSD cards fulfill all the promises of the SD card format, but in a size that would have been the stuff of spy movies only a decade ago. MicroSD cards are most commonly found in full-featured or "smart" cell phones, but can also be found in some music players and GPS navigation units. Duracell microSD cards come with adapters to convert the memory to either a miniSD or full-sized SD shape. This feature enables the cards to be fully operational in virtually any SD-capable device.