... by electronic shock, encrypted and limits of authority, upgrading of firmware, electromagnetic interference, and so on. Capacities available16MB,32MB, 64MB, 128MB ... ,512MB,1GB, 2GB, 4GB, 8GB, 16GB,32GBUSB chipsHigh quality Samsung/Hynix/Micron Grade A real chipsOperation systemWindows 7/Vista/XP/2000 ...