USB 2.0 Hi-Speed Cipher Shield^TM 2.5" Disk-On-The-GO Lite Hard Drive, 4500-5400RPM 

Available in: (Link to various model and part number)
Encryption - 40 bit, 64 bit, 128 bit, and 192 bit
Drive Capacity - 20GB, 40GB, 60GB, 80GB

Features:

Encryption key on removable hardware key; can be removed and stored away to prevent unauthorized access
Easy Windows Plug-n-Play, supports hot plugging and dynamic reconfiguration
Using NIST (National Institute of Science and Technology) approved DES/Triple DES/AES hardware encryption algorithm
Faster, easier to use, and more secure than software encryption
Operates transparently to the OS; does not require drivers
64, 128, 192 bits key depending on model
Compliant with USB Hi-Speed standard with up to 480Mbits/sec data rate, 40 times faster than USB 1.1
Supports up to 128 devices on the USB bus
Self-powered, DC adapter included

System Requirements:

PentiumR II 266MHz processor or higher (Pentium II 800MHz or higher recommended)
Microsoft WindowsR 98SE, 2000, ME, or XP
64MB RAM, 128MB or higher recommended
USB 1.1 port - drive will run at Full Speed or
USB Hi-Speed port - drive will run at High Speed or

Package Contents:

1 USB 2.0 CipherShield 2.5" Lite Hard Drive
1 A to B USB Cable
1 User Manual
1 Full range switching DC adapter