CalDigit VR2 - Dual HDD Hardware RAID - eSATA, USB 3.0/2.0, FireWire 800 & 400 (4TB) Quad Interface - USB 3.0/2.0, eSATA, Firewire 800 & 400 Hardware RAID - Supports RAID 0, 1, JBOD, and SPAN modes Removable Drives - Hot swappable drive modules for easy replacement LED Display - Change RAID settings without additional software Active Cooling - Efficient temperature controlled fan reduces heat and keeps noise levels minimal