Sans Digital Rackmount eSATA External Hard Drive Enclosure ER104UT+B HDD Slots 4 Hot-Swappable 3.5-Inch Built-in rackmount bracket, four hot-swappable trays 1U 4 bay Rackmount with over 200MB/s in RAID 5 performance USB 3.0 and eSATA host intereface, supporting PC, Mac and Linux Hardware RAID supporting RAID 0, 1, 1+0, 3, 5 and CLONE with hot spare.