USB Flash Disk Specifications and Features: Capacity available and optional: 64MB/128MB/256MB/512MB/1GB/2GB/4GB; USB 2.0; Portable data storage device; NAND Flash memory chip embedded; Original brandnew flash chip (Samsung/Hynix/Micron/Infenion) Driverless under Windows ME / 2000 / XP, Mac 9.0 and above, Linux 2.4 and above. Hot plug and play; Password protection; MLC Flash chip: Writting/Reading speed: 2-3Mbps/8-10Mbps; SLC Flash chip: Writting/Reading speed: 6-8Mbps/10-12Mbps