Sandisk Memory Stick Pro Duo - 4GB. SanDisk Standard Memory Stick PRO Duo cards give you plenty of room to capture and store your world in Sony and Sony Ericsson digital devices. And they're built to last, so you can be confident that all of your precious files will be there when you want them.
SanDisk's Memory Stick PRO Duo is half the size of a standard-size Memory Stick PRO media and it offers the same technologies including high speed data transfer, built-in MagicGate, and high capacities.
The Memory Stick PRO Duo is the ideal solution for the most portable devices such as pocket-size digital cameras and with the use of Adaptor, it can be used in all PRO-compatible devices and the Sony Playstation Portable (PSP)