Professional Kingston MicroSDHC 4GB (4 Gigabyte) Card for Casio G'zOne Rock C731 Smartphone Phone with custom formatting and Standard SD Adapter. (SDHC Class 4 Certified) Professional Kingston MicroSDHC 4GB (4 Gigabyte) Card for Share your content collections with friends, family and colleagues easily. Kingstons removable storage solution specifically designed for mobile phones with expansion slots. Its ultra-small size consumes very little power from your handset, to give you longer battery life on your phone. Now you can instantly move pictures between multiple devices for sharing and printing using this card as well.