The manufacturer, Network Appliance, Inc., was founded in 1992 when its founders left Auspex Systems, Inc., at that time the leading provider of Network Attached Storage systems, or NAS. As NetApp began to develop its customer base in the mid-90s, surplus used NetApp hardware first started to become available. In 1998, Union Computer made its first major acquisition of used NetApp hardware which consisted of dozens of F330 Filer heads and many hundreds of 2gb and 4gb NetApp disk drives which had been helping to drive the early growth of America Online's IT infrastructure.