The HDD Extension Unit from i-PRO is an extension unit designed for the WJ-NX400K recorder (sold separately). It can be rack mounted and contains up to nine front-loading hard disk drives, each supporting a capacity of up to 6TB (9 x 6TB preinstalled) Up to nine 3.5″ HDD drives at 6TB each for a total of 54TB storage. They can be used in a RAID (Redundant Arrays of Independent Disks) configuration to improve fault tolerance. This HDD extension unit can only operate with the WJ-NX400K recorder, which can support up to five extension units.
The Hard Disk Drive Extension Unit holds up to 9 drives. It is available in 3TB, 4TB, 6TB, 27TB, 36TB and 54TB configurations.