Sony 4GB Memory Stick PRO™ Duo (MSX-M4GS)

Capacity: This Memory Stick may be one of the smallest digital storage devices available, but it has a huge amount of storage—up to 4 GB. It writes data at up to 160Mbps (20MB/sec).

Compatibility: Designed especially for digital cameras, portable audio devices and the PSP Handheld Entertainment System. The included adapter can be used in most devices that use full-sized Memory Stick PRO media, making it perfect for new and old devices