The PA-220 provides you interactive visibility and control of applications, users, and content at throughput speeds of up to 500 Mbps. You get redundant power input for increased reliability, a fanless design for quiet operation, and solid state disks to remove any moving parts. The PA-220 also simplifies the deployments of large numbers of firewalls through the USB port.
For new purchases, consider the PA-440 to PA-460 instead.