The Lenovo USB Ultra Secure Memory Keys -- 4 GB (1) and 8 GB are thumb-size, lightweight, USB flash memory storage devices that let you share data between ThinkPad and desktop systems with a functional USB port. (1) GB = 1 billion bytes when referring to storage capacity; accessible capacity is less.Features & Benefits:Windows 7 Compliant Very small form factor; attachable to a key ring via the key cap or the main body of the memory key Security enabled for password protection of all stored data AES encryption of all stored data No software required to be installed since all security and encryption is done through hardware