Windows 98 supports write-behind caching for removable disk drives. VTOC was originally designed for removable disk packs. The Model 655 disk drive used a removable disk pack. RDX removable disk technology consists of portable disk cartridges and an RDX dock. Formerly, removable disk packs were common, allowing storage capacity to be expanded. A removable disk pack can be easily exchanged with another pack in a few seconds. On a Windows computer, a Hi-MD device is listed as "Removable Disk" in "My Computer".