This article is from the storage FAQ part2, by Rodney D. Van Meter with numerous contributions by others.
At Comdex '94 in Vegas, Metrum (now MountainGate) introduced the D-900 (900 cartridges, up to 20 drives, 9TB uncompressed for DLT-2000) and D-360 (360 cartridges, up to 8 drives, 3.6 TB uncompressed for DLT-2000) DLT autochangers. There is an expansion unit with 480 cartridges which may hold two drives. Up to eight D-360 or D-480 units can be connected via passthrough. They also introduced 28 and 60 cartridge DLT autochangers. Customer shipments starting in early '95. See above under VHS for contact info.