Sony 4 GB Memory Stick PRO DUO Media (MSX-M4GS) (Retail Package) 4 GB storage capacity with 3.66 GB available Minimum write speeds of 15 Mbps Includes adapter for use with Memory Stick PRO compatible devices Transfer speed up to 160 Mbps 4 GB of storage for your compact digital camera, portable audio device, or PSP Handheld Entertainment System not for camcorders DCR series