SanDisk is proud to announce the newest format and capacity to the SD card family: Secure Digital High Capacity (SDHC) 4GB flash card, tested and rated Class 2, for speed and performance. The SD Card is a highly secure stamp-sized flash memory card, which can be used in a variety of digital products; digital music players, cellular phones, handheld PCs, digital cameras, digital video camcorders, smart phones, car navigation systems and electronic books. Non-volatile solid-state; no moving parts maximizes battery power. Data is not lost when power is turned off User selectable mechanical write protect switch on the exterior card casing