not needed. In a change of strategy, HP LTO Gen 2, 3 and 4 drives will always clean when a Universal Cleaning Cartridge is inserted, whether the drive requires cleaning or not. Mechanisms , compliance-verified licensed manufacturers of current LTO technology mechanisms are IBM, Hewlett-Packard, and Quantum, although both Hewlett Packard and Quantum have stopped new development of drive mechanisms. The mechanisms, also known as tape drives or streamers, are available in Full-height and Half-height form factors. These drives are frequently packaged into external desktop enclosures or carriers that fit into a robotic tape library. Sales and market In the course of its existence, LTO has succeeded in completely displacing all other low-end/mid-range tape technologies such as AIT, DLT, DAT/DDS, and VXA. And after the exit of Oracle StorageTek T10000 of the high-end market, only the IBM 3592 series is still under active development. LTO also competes against hard disk drives (HDDs), and its continuous improvement has prevented the predicted "death of tape" at the hands of disk. The presence of five certified media manufacturers and four certified mechanism manufacturers for a while produced a competitive market for LTO products. However, , there are only two manufacturers developing media, Sony and Fuji, and only IBM is developing mechanisms. The LTO organization publishes annual media shipments measured in both units and compressed capacity. In 2017, a record 108,457 petabytes (PB) of total tape capacity (compressed) shipped, an increase of 12.9 percent over the previous year. Cartridge unit shipments decreased to about 18 million units down from a peak of about 27 million units in 2008. Public information on tape drive sales is not readily available. Unit shipment peaked at about 800,000 units in 2008, but have declined since then to about 400,000 units in 2010, and to less than 250,000 by the end of 2018 As HDD prices have dropped, disk has become cheaper relative to tape drives and cartridges. , at any capacity, the cost of a new LTO tape drive plus one cartridge is much greater than that of a new HDD of the same or greater storage capacity. However, most new tape cartridges still have a lower price per gigabyte than HDDs, so that at very large subsystem capacities, the total price of tape-based subsystems can be lower than HDD based subsystems, particularly when the higher operating costs of HDDs are included in any calculation. Tape is also