This BUSlink 4-Bay RAID hard drive supports large capacity and dual USB 3.0+eSATA interface. It supports Intelligent RAID function: RAID 0, RAID 3, RAID 5, RAID 10, and Large. Removable HDD trays support hot-plug replacement of drives (only for RAID with redundancy mode). HDD intelligent sleep function is supported. The LCM display and buttons support convenient setting of RAID modes and status display. Optional password allows locking of RAID settings. Cooling fan maintain safe operating temperature. Included CD allows software control of RAID mode and status display in PC. Skid proof and shockproof rubber feet mat ensure safe operation. DAS Storage System offers maximum storage efficiency and convenience Holds up to 4 HDDs Through RAID levels (0, 3, 5, 10, large), RAID provides data reliability, fault tolerance and improves overall performance Through RAID levels (0, 3, 5, 10, large), RAID provides data reliability, fault tolerance and improves overall performance 256-bit AES Encryption feature for maximum efficiency and convenience