12TB is the largest hard drive size that has been tested in High-Rely classic Media. 2TB drives in MPac media (2 per cartridge for 4TB total), 12TB in RAIDPac Media (total 36TB with 3 drives in RAID0 mode). We are currently waiting to test 14TB 3.5″ in both High-Rely Classic and RAIDPacs and expect to ship these when they become commercially available.